0001564590-20-006373 | 10-K | XBRL Viewer

Summary of Significant Accounting Policies

NOTE 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Organization

McGrath RentCorp and its wholly-owned subsidiaries (the “Company”) is a California corporation organized in 1979. The Company is a diversified business to business rental company with four rental divisions; relocatable modular buildings, portable storage containers, electronic test equipment and liquid and solid containment tanks and boxes. Although the Company’s primary emphasis is on equipment rentals, sales of equipment occur in the normal course of business. The Company is comprised of four reportable business segments: modular building and portable storage segment (“Mobile Modular”), electronic test equipment segment (“TRS-RenTelco”), containment solutions for the storage of hazardous and non-hazardous liquids and solids segment (“Adler Tanks”) and classroom manufacturing division selling modular classrooms in California (“Enviroplex”).

Principles of Consolidation

The consolidated financial statements include the accounts of McGrath RentCorp and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.

Revenue Recognition

Lease revenues - Rental revenues from operating leases are recognized on a straight-line basis over the term of the lease for all operating segments. Rental billings for periods extending beyond period end are recorded as deferred income and are recognized in the period earned. Rental related services revenues are primarily associated with relocatable modular building and liquid and solid containment tanks and boxes leases. For modular building leases, rental related services revenues for modifications, delivery, installation, dismantle and return delivery are lease related because the payments are considered minimum lease payments that are an integral part of the negotiated lease agreement with the customer. These revenues are recognized on a straight-line basis over the term of the lease. Certain leases are accounted for as sales-type leases. For these leases, sales revenue and the related accounts receivable are recognized upon delivery and installation of the equipment and the unearned interest is recognized over the lease term on a basis which results in a constant rate of return on the unrecovered lease investment. Other revenues include interest income on sales-type leases and rental income on facility leases.

Non-lease revenues - Sales revenue is recognized upon delivery and installation of the equipment to customers. Certain leases are accounted for as sales-type leases. For these leases, sales revenue and the related accounts receivable are recognized upon delivery and installation of the equipment and the unearned interest is recognized over the lease term on a basis which results in a constant rate of return on the unrecovered lease investment.

Other revenue is recognized when earned and primarily includes interest income on sales-type leases, rental income on facility leases and certain logistics services.

Sales taxes charged to customers are reported on a net basis and are excluded from revenues and expenses.

Depreciation of Rental Equipment

Rental equipment is depreciated on a straight-line basis for financial reporting purposes and on an accelerated basis for income tax purposes. The costs of major refurbishment of relocatable modular buildings, portable storage containers and tanks and boxes are capitalized to the extent the refurbishment significantly adds value to, or extends the life of the equipment. Maintenance and repairs are expensed as incurred.

The estimated useful lives and residual values of the Company’s rental equipment used for financial reporting purposes are as follows:

Relocatable modular buildings		18 years, 50% residual value
Relocatable modular accessories		3 to 18 years, no residual value
Blast resistant modules		20 years, no residual value
Portable storage containers		25 years, 62.5% residual value
Electronic test equipment and accessories		1 to 8 years, no residual value
Liquid and solid containment tanks and boxes and accessories		3 to 20 years, no residual value

Costs of Rental Related Services

Costs of rental related services are primarily associated with relocatable modular building leases and liquid and solid containment tank and boxes. Modular building leases primarily consist of costs for services to be provided under the negotiated lease agreement for delivery, installation, modifications, skirting, additional site-related work, and dismantle and return delivery. Costs related to these services are recognized on a straight-line basis over the term of the lease. Costs of rental related services associated with liquid and solid containment solutions consists of costs of delivery, removal and cleaning of the tanks and boxes. These costs are recognized in the period the service is performed.

Impairment of Long-Lived Assets

The Company evaluates the carrying value of rental equipment and identifiable definite lived intangible assets for impairment whenever events or circumstances have occurred that would indicate the carrying amount may not be fully recoverable. A key element in determining the recoverability of long-lived assets is the Company’s outlook as to the future market conditions for its rental equipment. If the carrying amount is not fully recoverable, an impairment loss is recognized to reduce the carrying amount to fair value. The Company determines fair value based upon the condition of the rental equipment and the projected net cash flows from its rental and sale considering current market conditions. Goodwill and identifiable indefinite lived assets are evaluated for potential impairment annually or when circumstances indicate potential impairment may have occurred. Impairment losses, if any, are determined based upon the excess of carrying value over the estimated fair value of the asset. There were no impairments of long-lived assets during the year ended December 31, 2019. The Company recorded an impairment of modular rental equipment of $0.1 million and $1.6 million for the years ended December 31, 2018 and 2017, respectively.

Other Direct Costs of Rental Operations

Other direct costs of rental operations include direct labor, supplies, repairs, insurance, property taxes, license fees, impairment of rental equipment and certain modular lease costs charged to customers in the negotiated rental rate, which are recognized on a straight-line basis over the term of the lease.

Cost of Sales

Cost of sales in the Consolidated Statements of Income includes the carrying value of the equipment sold and all direct costs associated with the sale.

Warranty Reserves

Sales of new relocatable modular buildings, portable storage containers, electronic test equipment and related accessories and liquid and solid containment tanks and boxes not manufactured by the Company are typically covered by warranties provided by the manufacturer of the products sold. The Company typically provides limited 90-day warranties for certain sales of used rental equipment and one-year warranties on equipment manufactured by Enviroplex. Although the Company’s policy is to provide reserves for warranties when required for specific circumstances, the Company has not found it necessary to establish such reserves to date as warranty costs have not been significant.

Property, Plant and Equipment

Property, plant and equipment are stated at cost, net of accumulated depreciation. Depreciation is recognized on a straight-line basis for financial reporting purposes, and on an accelerated basis for income tax purposes. Depreciation expense for property, plant and equipment is included in “Selling and administrative expenses” and “Rental related services” in the Consolidated Statements of Income. Maintenance and repairs are expensed as incurred.

Property, plant and equipment consist of the following:

(dollar amounts in thousands)	Estimated useful life		December 31,
	in years		2019			2018
Land	Indefinite		$	54,423		$	50,689
Land improvements	20 – 50			52,325			50,064
Buildings		30		29,848			29,359
Furniture, office and computer equipment	3 – 10			36,610			33,081
Vehicles and machinery	5 – 25			41,877			38,199
				215,083			201,392
Less accumulated depreciation				(84,308	)		(77,118	)
				130,775			124,274
Construction in progress				272			2,625
			$	131,047		$	126,899

Property, plant and equipment depreciation expense was $8.2 million, $8.0 million and $7.6 million for the years ended December 31, 2019, 2018 and 2017, respectively. Construction in progress at December 31, 2019 and 2018 consisted primarily of costs related to acquisition of land and land improvements and information technology upgrades.

Capitalized Software Costs

The Company capitalizes certain development costs incurred in connection with its internal use software. Costs incurred in the preliminary stages of development are expensed as incurred. Once an application has reached the development stage, direct internal and external costs are capitalized until the software is substantially complete and ready for its intended use. These costs generally include external direct costs of materials and services consumed in the project and internal costs, such as payroll and benefits of those employees directly associated with the development of the software. Maintenance, training and post implementation costs are expensed as incurred. The Company also capitalizes costs related to specific upgrades and enhancements when it is probable the expenditures will result in additional functionality. Capitalized software costs are included in property, plant and equipment. The Company capitalized $3.0 million and $0.1 million in internal use software during the years ended December 31, 2019 and 2018, respectively.

Advertising Costs

Advertising costs are expensed as incurred. Total advertising expenses were $3.6 million, $3.2 million and $2.9 million for the years ended December 31, 2019, 2018 and 2017.

Income Taxes

Income taxes are accounted for using an asset and liability approach. Deferred tax assets and liabilities are recorded for the effect of temporary differences between the tax basis of assets and liabilities and their reported amounts in the consolidated financial statements. Deferred tax assets and deferred tax liabilities are adjusted to the extent necessary to reflect tax rates expected to be in effect when temporary differences reverse. Adjustments may be required to deferred tax assets and deferred tax liabilities due to changes in tax laws and audit adjustments by tax authorities. A valuation allowance would be established if, based on the weight of available evidence, management believes that it is more likely than not that some portion or all of a recorded deferred tax asset would not be realized in future periods. To the extent adjustments are required in any given period, the adjustments would be included within the “Provision for income taxes” in the Consolidated Statements of Income.

Goodwill and Intangible Assets

Purchase prices of acquired businesses are allocated to the assets and liabilities acquired based on the estimated fair values on the respective acquisition dates. Based on these values, the excess purchase prices over the fair value of the net assets acquired are allocated to goodwill and other intangible assets. Intangible assets related to customer relationships are amortized over eleven years. At December 31, 2019 and 2018, goodwill and trade name intangible assets which have indefinite lives totaled $34.1 million and $33.7 million, respectively.

The Company assesses potential impairment of its goodwill and intangible assets when there is evidence that events or circumstances have occurred that would indicate the recovery of an asset’s carrying value is unlikely. The Company also assesses

potential impairment of its goodwill and intangible assets with indefinite lives on an annual basis regardless of whether there is evidence of impairment. If indicators of impairment were to be present in intangible assets used in operations and future discounted cash flows were not expected to be sufficient to recover the assets’ carrying amount, an impairment loss would be charged to expense in the period identified. The amount of an impairment loss would be recognized as the excess of the asset’s carrying value over its fair value. Factors the Company considers important, which may cause impairment include, among others, significant changes in the manner of use of the acquired asset, negative industry or economic trends, and significant underperformance relative to historical or projected operating results.

The impairment review of the Company’s goodwill is performed by first assessing qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step impairment test. In the first step, the fair value of the reporting unit is compared to its carrying value to determine if the goodwill is impaired. If the fair value of the reporting unit exceeds the carrying value of the net assets assigned to that unit, then goodwill is not impaired and no further testing is required. If the carrying value of the net assets assigned to the reporting unit were to exceed its fair value, then the second step is performed in order to determine the implied fair value of the reporting unit’s goodwill and an impairment loss is recorded for an amount equal to the difference between the implied fair value and the carrying value of the goodwill.

The Company conducted its annual impairment analysis in the fourth quarter of its fiscal year. The impairment analysis did not result in an impairment charge for the fiscal years ended 2019, 2018 or 2017. Determining the fair value of a reporting unit is judgmental and involves the use of significant estimates and assumptions. The Company based its fair value estimates on assumptions that it believes are reasonable but are uncertain and subject to changes in market conditions.

Earnings Per Share

Basic earnings per share (“EPS”) is computed as net income divided by the weighted average number of shares of common stock outstanding for the period. Diluted EPS is computed assuming conversion of all potentially dilutive securities including the dilutive effects of stock options, unvested restricted stock awards and other potentially dilutive securities. The table below presents the weighted-average common stock used to calculate basic and diluted earnings per share:

(in thousands)	Year Ended December 31,
	2019		2018		2017
Weighted-average common stock for calculating basic earnings per share		24,250		24,141		23,999
Effect of potentially dilutive securities from equity-based compensation		373		399		270
Weighted-average common stock for calculating diluted earnings per share		24,623		24,540		24,269

In 2017, there were 7,000 options to purchase common stock that were not included in the computation of diluted earnings per share, as their effect would have been anti-dilutive. There were no shares excluded in 2019 and 2018.

The Company has in the past made purchases of shares of its common stock from time to time in over-the-counter market (NASDAQ) transactions, through privately negotiated, large block transactions and through a share repurchase plan, in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934. In August 2015, the Company’s Board of Directors authorized the Company to repurchase 2,000,000 shares of the Company's outstanding common stock. The amount and time of the specific repurchases are subject to prevailing market conditions, applicable legal requirements and other factors, including management’s discretion. All shares repurchased by the Company are canceled and returned to the status of authorized but unissued shares of common stock. There can be no assurance that any authorized shares will be repurchased and the repurchase program may be modified, extended or terminated by the Board of Directors at any time. There were no repurchases of common stock during the twelve months ended December 31, 2019, 2018 and 2017. As of December 31, 2019, 1,592,026 shares remain authorized for repurchase.

Accounts Receivable and Concentration of Credit Risk

The Company’s accounts receivable consist of amounts due from customers for rentals, sales, financed sales and unbilled amounts for the portion of modular building end-of-lease services earned, which were negotiated as part of the lease agreement. Unbilled receivables related to end-of-lease services, which consists of dismantle and return delivery of buildings, were $37.2 million at December 31, 2019 and $32.3 million at December 31, 2018. The Company sells primarily on 30-day terms, individually performs

credit evaluation procedures on its customers on each transaction and will require security deposits from its customers when a significant credit risk is identified. The Company records an allowance for doubtful accounts in amounts equal to the estimated losses expected to be incurred in the collection of the accounts receivable. The estimated losses are based on historical collection experience in conjunction with an evaluation of the current status of the existing accounts. Customer accounts are written off against the allowance for doubtful accounts when an account is determined to be uncollectable. The allowance for doubtful accounts activity was as follows:

(in thousands)	2019			2018
Beginning balance, January 1	$	1,883		$	1,920
Provision for doubtful accounts		1,013			581
Write-offs, net of recoveries		(1,013	)		(618	)
Ending balance, December 31	$	1,883		$	1,883

Financial instruments that potentially subject the Company to concentration of credit risk consist primarily of trade accounts receivable. From time to time, the Company maintains cash balances in excess of the Federal Deposit Insurance Corporation limits.

Fair Value of Financial Instruments

The Company believes that the carrying amounts for cash, accounts receivable, accounts payable and notes payable approximate their fair values except for fixed rate debt included in notes payable which has an estimated fair value of $101.4 million and $99.0 million compared to the recorded value of $100.0 million as of December 31, 2019 and 2018, respectively. The estimates of fair value of the Company’s fixed rate debt are based on the borrowing rates currently available to the Company for bank loans with similar terms and average maturities.

Foreign Currency Transactions and Translation

The Company's Canadian subsidiary, TRS-RenTelco Inc., a British Columbia corporation (“TRS-Canada”), functions as a branch sales office for TRS-RenTelco in Canada. The functional currency for TRS-Canada is the U.S. dollar. Foreign currency transaction gains and losses of TRS-Canada are reported in the results of operations in the period in which they occur.

The Company’s Indian subsidiary, TRS-RenTelco India Private Limited (“TRS-India”), functioned as a rental and sales office for TRS-RenTelco in India, which commenced its closure during 2017. The functional currency for TRS-India is the Indian Rupee. All assets and liabilities of TRS-India are translated into U.S. dollars at period-end exchange rates and all income statement amounts are translated at the average exchange rate for each month within the year.

Currently, the Company does not use derivative instruments to hedge its economic exposure with respect to assets, liabilities and firm commitments as the foreign currency transactions and risks to date have not been significant.

Share-Based Compensation

The Company measures and recognizes the compensation expense for all share-based awards made to employees and directors, including stock options, stock appreciation rights (“SARs”) and restricted stock units (“RSUs”), based upon estimated fair values. The fair value of stock options and SARs is estimated on the date of grant using the Black-Scholes option pricing model and for RSUs based upon the fair market value of the underlying shares of common stock as of the date of grant. The Company recognizes share-based compensation cost ratably on a straight-line basis over the requisite service period, which generally equals the vesting period. For performance-based RSUs, compensation costs are recognized when vesting conditions are met. In addition, the Company estimates the probable number of shares of common stock that will be earned and the corresponding compensation cost until the achievement of the performance goal is known. The Company records share-based compensation costs in “Selling and administrative expenses” in the Consolidated Statements of Income. The Company recognizes a benefit from share-based compensation in the Consolidated Statements of Shareholders’ Equity if an incremental tax benefit is realized. Further information regarding share-based compensation can be found in “Note 6 –Benefit Plans”.

Use of Estimates

The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions in determining reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during each period presented. Actual results could differ from those estimates. The most significant estimates included in the financial statements are the future cash flows and fair values used to determine the recoverability of the rental equipment and

identifiable definite lived intangible assets carrying value, the various assets’ useful lives and residual values, and the allowance for doubtful accounts.

New Accounting Pronouncements

12 Months Ended

Dec. 31, 2019

New Accounting Pronouncements

NOTE 2. NEW ACCOUNTING PRONOUNCEMENTS

In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2016-13, Financial Instruments – Credit Losses (Topic 326), requiring companies to present assets held at amortized cost and available for sale debt securities net of the amount expected to be collected. This new guidance requires the measurement of expected credit losses to be based on relevant information from past events, including historical experiences, current conditions and reasonable and supportable forecasts that affect collectability. This guidance does not apply to receivables arising from operating leases and will be effective for fiscal years and interim periods beginning after December 15, 2019. The Company does not expect the adoption of this ASU to have a material impact on its consolidated financial statements.

In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, expected to reduce cost and complexity related to the accounting for income taxes. The ASU removes specific exceptions to the general principles in Topic 740 in Generally Accepted Accounting Principles (GAAP). It eliminates the need for an organization to analyze whether the following apply in a given period: exception to the incremental approach for intra-period tax allocation; exceptions to accounting for basis differences when there are ownership changes in foreign investments; and exception in interim period income tax accounting for year-to-date losses that exceed anticipated losses. The ASU also improves financial statement preparers’ application of income tax-related guidance and simplifies GAAP for: franchise taxes that are partially based on income; transactions with a government that result in a step up in the tax basis of goodwill; separate financial statements of legal entities that are not subject to tax; and enacted changes in tax laws in interim periods. The Company is evaluating the impact of this guidance on its consolidated financial statements.

Implemented Accounting Pronouncements

12 Months Ended

Dec. 31, 2019

Accounting Changes And Error Corrections [Abstract]

Implemented Accounting Pronouncements

NOTE 3. IMPLEMENTED ACCOUNTING PRONOUNCEMENTS

Lessee

The Company adopted ASU No. 2016-02, Leases (Subtopic 842-10) effective January 1, 2019. Under the new guidance, lessees are required to recognize the following for all leases (with the exception of short-term leases) on the commencement date: a) lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and b) right-of-use (“ROU”) asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. The Company adopted the new guidance using the transition method that allowed it to initially apply this guidance on the adoption date. The adoption did not result in a cumulative-effect adjustment to the Company’s opening retained earnings. Because of the transition method the Company used to adopt the new guidance, historical financial information was not updated and the financial disclosures required under the new standard are not provided for periods prior to January 1, 2019. The new guidance contains additional optional transition practical expedients intended to simplify adoption. The Company elected the package of practical expedients that allows for not reassessing: (1) whether any expired or existing contracts are or contain leases, (2) the lease classification for any expired or existing leases and (3) initial direct costs for any expired or existing leases.

The Company leases real estate for certain of its branch offices and rental equipment storage yards, vehicles and equipment used in its rental operations. The Company determines if an arrangement is a lease at inception. The Company has leases with lease and non-lease components, which are accounted for separately. ROU assets and liabilities are recognized on the commencement date based on the present value of lease payments over the lease term. Variable lease payments are excluded from the ROU assets and lease liabilities and are recognized in the period in which the obligation for those payments is incurred, which are not material. The Company’s lease agreements do not contain any material residual value guarantees or material restrictive covenants. The Company uses the interest rate stated in the lease as the discount rate. If the interest rate is not stated, the Company uses its incremental borrowing rate based on information available on lease commencement date in determining the present value of lease payments. Many of the Company’s real estate lease agreements include options to extend the lease, which are not included in the minimum lease terms unless they are reasonably certain to be exercised. These leases include one or more options to renew, with renewal terms that may extend the lease term from one to three years. The amount of payments associated with such options is not material. Short-term leases are leases having a term of twelve months or less and exclude leases with a lease term of one month or less. The Company recognizes short-term leases on a straight-line basis and does not record a related ROU asset or liability for such leases. The adoption of the new guidance resulted in the recording of $10.0 million of ROU assets and operating lease liabilities, which were recorded in Prepaid expenses and other assets and Accounts payable and accrued liabilities on the Company’s Condensed Consolidated Balance Sheet.

During the year ended December 31, 2019, operating lease expense was $3.8 million, which includes short term lease expense of $0.2 million. At December 31, 2019, the weighted-average remaining lease term for operating leases was 3.8 years and the

weighted average discount rate was 4.38%. The Company had no sub-lease income during the year ended December 31, 2019, and did not have any finance leases as of December 31, 2019.

Supplemental cash flow information related to leases was as follows:

(in thousands)	Year Ended
	December 31, 2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	3,568

Right of use assets obtained in exchange for lease obligations:
Operating leases	$	2,728

As of December 31, 2019, maturities of operating lease liabilities were as follows:

(in thousands)
Year ended December 31,
2020	$	3,350
2021		2,794
2022		1,958
2023		1,458
2024		915
Thereafter		293
Total lease payments		10,768
Less imputed interest		(823	)
	$	9,945

Lessor

As a lessor, the Company’s recognition of lease revenue remained consistent with previous guidance. As a result, the adoption of the lease standard did not have an impact on the Company’s current and previously reported results in the Company’s Condensed Consolidated Statements of Income.

The Company’s equipment rentals for each of its operating segments are governed by agreements that detail the lease terms and conditions. The determination of whether these contracts with customers contain a lease generally does not require significant judgement. The Company accounts for these rentals as operating leases. These leases do not include material amounts of variable payments and the Company has made the accounting policy election to exclude all taxes assessed by a governmental authority. The Company generally does not provide an option for the lessee to purchase the rented equipment at the end of the lease term, thus, does not generate material revenue from sales of equipment under such options. Initial lease terms vary in length based upon customer needs and generally range from one to sixty months. Customers have the option to keep equipment on rent beyond the initial lease term on a month-to month basis based upon their needs. All of the Company’s rental products have long useful lives relative to the typical rental term with the original investment typically recovered in approximately three to five years. The rental products are typically rented for a majority of the time owned and a significant portion of the original investment is recovered when sold from inventory. The Company’s lease agreements do not contain residual value guarantees or restrictive covenants.

As of December 31, 2019, maturities of operating lease payments to be received in 2020 and thereafter were as follows:

(in thousands)
Year Ended December 31,
2020	$	92,821
2021		30,926
2022		8,922
2023		2,145
2024		877
Thereafter		37
	$	135,728

In the year ended December 31, 2019, the Company’s lease revenues were $411.0 million, consisting of $407.6 of operating lease revenues and $3.4 million of finance lease revenues. The Company has entered into finance leases to finance certain equipment sales to customers. The lease agreements have a bargain purchase option at the end of the lease term. For these leases, sales revenue and the related accounts receivable are recognized upon delivery and installation of the equipment and the unearned interest is recognized over the lease term on a basis, which results in a constant rate of return on the unrecovered lease investment. For the year ended December 31, 2019, the Company’s finance lease revenues included $3.1 million of sales revenues and $0.3 million of interest income. The minimum lease payments receivable and the net investment are included in Accounts receivable on the Company’s Consolidated Balance Sheet for such leases, which were as follows:

(in thousands)	December 31, 2019
Gross minimum lease payments receivable	$	3,218
Less – unearned interest		(289	)
Net investment in finance lease receivables	$	2,929

As of December 31, 2019, the future minimum lease payments under non-cancelable finance leases to be received in 2020 and thereafter were as follows:

(in thousands)
Year Ended December 31,
2020	$	2,345
2021		629
2022		184
2023		50
2024		10
Thereafter		—
Total minimum future lease payments to be received	$	3,218

Revenue Recognition

12 Months Ended

Dec. 31, 2019

Revenue From Contract With Customer [Abstract]

Revenue Recognition

NOTE 4. REVENUE RECOGNITION

The Company’s accounting for revenues is governed by two accounting standards. The majority of the Company’s revenues are considered lease or lease related and are accounted for in accordance with Topic 840, Leases. Revenues determined to be non-lease related are accounted for in accordance with ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), which was adopted by the Company on January 1, 2018. The Company utilized the modified retrospective method of adoption and there was no impact on its condensed consolidated financial statements, nor was there a cumulative effect of initially applying the new standard. The Company accounts for revenues when approval and commitment from both parties have been obtained, the rights of the parties are identified, payment terms are identified, the contract has commercial substance and collectability of consideration is probable. The Company typically recognizes non-lease related revenues at a point in time because the customer does not simultaneously consume the benefits of the Company’s promised goods and services, or performance obligations, and obtain control when delivery and installation are complete. For contracts that have multiple performance obligations, the transaction price is allocated to each performance obligation in the contract based on the Company’s best estimate of the standalone selling prices of each distinct performance obligation in the contract. The standalone selling price is typically determined based upon the expected cost plus an estimated margin of each performance obligation.

The Company generally rents and sells to customers on 30 day payment terms. The Company does not typically offer variable payment terms, or accept non-monetary consideration. Amounts billed and due from the Company’s customers are classified as Accounts receivable on the Company’s consolidated balance sheet. For certain sales of modular buildings, progress payments from the customer are received during the manufacturing of new equipment, or the preparation of used equipment. The advance payments are not considered a significant financing component because the payments are used to meet working capital needs during the contract and to protect the Company from the customer failing to adequately complete their obligations under the contract. These contract liabilities are included in Deferred income on the Company’s consolidated balance sheet and totaled $17.5 million and $15.7 million at December 31, 2019 and 2018, respectively. Sales revenues totaling $10.2 million were recognized during the year ended December 31, 2019, which were included in the contract liability balance at December 31, 2018. For certain modular building sales, the customer retains a small portion of the contract price until full completion of the contract, which results in revenue earned in excess of billings. These unbilled contract assets are included in Accounts receivable on the Company’s consolidated balance sheet and totaled $1.0 million and $1.4 million at December 31, 2019 and 2018, respectively.

Lease Revenues

Rental revenues from operating leases are recognized on a straight-line basis over the term of the lease for all operating segments. Rental billings for periods extending beyond period end are recorded as deferred income and are recognized in the period earned. Rental related services revenues are primarily associated with relocatable modular building and liquid and solid containment tanks and boxes leases. For modular building leases, rental related services revenues for modifications, delivery, installation, dismantle and return delivery are lease related because the payments are considered minimum lease payments that are an integral part of the negotiated lease agreement with the customer. These revenues are recognized on a straight-line basis over the term of the lease. Certain leases are accounted for as sales-type leases. For these leases, sales revenue and the related accounts receivable are recognized upon delivery and installation of the equipment and the unearned interest is recognized over the lease term on a basis which results in a constant rate of return on the unrecovered lease investment. Other revenues include interest income on sales-type leases and rental income on facility leases.

Non-Lease Revenues

Non-lease revenues are recognized in the period when control of the performance obligation is transferred, in an amount that reflects the consideration the Company expects to be entitled to receive in exchange for those goods or services. For liquid and solid containment solutions, portable storage containers and electronic test equipment, rental related services revenues for delivery and return delivery are considered non-lease revenues.

Sales revenues are typically recognized at a point in time, which occurs upon the completion of delivery, installation and acceptance of the equipment by the customer. Accounting for non-lease revenues requires judgment in determining the point in time the customer gains control of the equipment and the appropriate accounting period to recognize revenue.

Sales taxes charged to customers are reported on a net basis and are excluded from revenues and expenses.

The following table disaggregates the Company’s revenues by lease (within the scope of Topic 840) and non-lease revenues (within the scope of Topic 606) and the underlying service provided for the three years ended December 31, 2019, 2018 and 2017:

(in thousands)	Mobile Modular			TRS- RenTelco		Adler Tanks			Enviroplex		Consolidated
Year Ended December 31,
2019
Leasing	$	234,032		$	108,044	$	68,917		$	—	$	410,993
Non-lease:
Rental related services		18,964			2,599		27,634			—		49,197
Sales		47,045			18,995		1,266			39,814		107,120
Other		969			1,845		106			—		2,920
Total non-lease		66,978			23,439		29,006			39,814		159,237
Total revenues	$	301,010		$	131,483	$	97,923		$	39,814	$	570,230

2018
Leasing	$	200,214		$	94,345	$	70,653		$	—	$	365,212
Non-lease:
Rental related services		14,870			2,607		24,276			—		41,753
Sales		39,467			19,895		1,044			29,046		89,452
Other		23			1,810		80			—		1,913
Total non-lease		54,360			24,312		25,400			29,046		133,118
Total revenues	$	254,574		$	118,657	$	96,053		$	29,046	$	498,330

2017
Leasing	$	180,612		$	85,930	$	64,676		$	—	$	331,218
Non-lease:
Rental related services		13,331			2,358		24,322			—		40,011
Sales		37,434			18,137		2,362			31,369		89,302
Other		(111	)		1,619		(5	)		—		1,503
Total non-lease		50,654			22,114		26,679			31,369		130,816
Total revenues	$	231,266		$	108,044	$	91,355		$	31,369	$	462,034

Customer returns of rental equipment prior to the end of the rental contract term are typically billed a cancellation fee, which is recorded as rental revenue in the period billed. Sales of new relocatable modular buildings, portable storage containers, electronic test equipment and related accessories and liquid and solid containment tanks and boxes not manufactured by the Company are typically covered by warranties provided by the manufacturer of the products sold. The Company typically provides limited 90-day warranties for certain sales of used rental equipment and one-year warranties on equipment manufactured by Enviroplex. Although the Company’s policy is to provide reserves for warranties when required for specific circumstances, the Company has not found it necessary to establish such reserves to date as warranty costs have not been significant.

The Company’s incremental cost of obtaining lease contracts, which consists of salesperson commissions, are deferred and amortized over the initial lease term for modular building leases. Incremental costs for obtaining a contract for all other operating segments are expensed in the period incurred because the lease term is typically less than 12 months.

Notes Payable

12 Months Ended

Dec. 31, 2019

Debt Disclosure [Abstract]

Notes Payable

NOTE 5. NOTES PAYABLE

Notes payable consists of the following:

(in thousands)	December 31,
	2019			2018
Unsecured revolving lines of credit	$	193,459		$	198,603
3.68% Series B senior notes due in 2021		40,000			40,000
3.84% Series C senior notes due in 2022		60,000			60,000
		293,459			298,603
Unamortized debt issuance cost		(28	)		(39	)
	$	293,431		$	298,564

As of December 31, 2019, the future minimum payments under the unsecured revolving lines of credit, 3.68% Series B senior notes due in 2021 and 3.84% Series C senior notes due in 2022 are as follows:

(in thousands)
Year Ended December 31,
2020	$	—
2021		233,459
2022		60,000
	$	293,459

Unsecured Revolving Lines of Credit

In March 2016, the Company renewed its credit agreement with a syndicate of banks (the “Credit Facility”). The five-year facility matures on March 31, 2021 and replaced the Company’s prior $420.0 million unsecured revolving credit facility. The Credit Facility provides for a $420.0 million unsecured revolving credit facility (which may be increased to $620.0 million with $200.0 million of additional commitments), which includes a $25.0 million sublimit for the issuance of standby letters of credit and a $10.0 million sublimit for swing-line loans.

In March 2016, the Company entered into a Credit Facility Letter Agreement and a Credit Line Note in favor of MUFG Union Bank, N.A., extending its line of credit facility related to its cash management services (“Sweep Service Facility”) and increasing the facility size from $10.0 million to $12.0 million. The Sweep Service Facility matures on the earlier of March 31, 2021, or the date the Company ceases to utilize MUFG Union Bank, N.A. for its cash management services.

At December 31, 2019, under the Credit Facility and Sweep Service Facility, the Company had unsecured lines of credit that permit it to borrow up to $432.0 million of which $193.5 million was outstanding, and had capacity to borrow up to an additional $238.5 million. The Amended Credit Facility contains financial covenants requiring the Company to not (all defined terms used below not otherwise defined herein have the meaning assigned to such terms in the Amended Credit Facility):

•

Permit the Consolidated Fixed Charge Coverage Ratio of EBITDA to fixed charges as of the end of any fiscal quarter to be less than 2.50 to 1. At December 31, 2019, the actual ratio was 4.27 to 1.

•

Permit the Consolidated Leverage Ratio of funded debt to EBITDA at any time during any period of four consecutive fiscal quarters to be greater than 2.75 to 1. At December 31, 2019, the actual ratio was 1.24 to 1.

•

Permit Tangible Net Worth as of the end of any fiscal quarter of the Company to be less than the sum of (i) $246.1 million plus (ii) 25% of the Company’s Consolidated Net Income (as defined in the Amended Credit Facility) (but only if a positive number) for each fiscal quarter ended subsequent to December 31, 2011 plus (iii) 90% of the net cash proceeds from the issuance of the Company’s capital stock after December 31, 2011. At December 31, 2019, such sum was $388.1 million and the actual Tangible Net Worth of the Company was $598.5 million.

Amounts borrowed under the Credit Facility bear interest at the Company’s option at either: (i) LIBOR plus a defined margin, or (ii) the Agent bank’s prime rate (“base rate”) plus a margin. The applicable margin for each type of loan is measured based upon the Consolidated Leverage Ratio at the end of the prior fiscal quarter and ranges from 1.00% to 1.75% for LIBOR loans and 0% to 0.75% for base rate loans. In addition, the Company pays an unused commitment fee for the portion of the $420.0 million credit facility that is not used. These fees are based upon the Consolidated Leverage Ratio and range from 0.15% to 0.30%. As of December 31, 2019 and 2018, the applicable margins were 1.25% for LIBOR based loans, 0.25% for base rate loans and 0.20% for

unused fees. Amounts borrowed under the Sweep Service Facility are based upon the MUFG Union Bank, N.A. base rate plus an applicable margin and an unused commitment fee for the portion of the $12.0 million facility not used. The applicable base rate margin and unused commitment fee rates for the Sweep Service Facility are the same as for the Amended Credit Facility. The following information relates to the lines of credit for each of the following periods:

3.68% Senior Notes Due in 2021

On March 17, 2014, the Company issued and sold to the Purchasers a $40.0 million aggregate principal amount of its 3.68% Series B Senior Notes (the “Series B Senior Notes”) pursuant to the terms of the Note Purchase Agreement, as amended. The Series B Senior Notes are an unsecured obligation of the Company, bear interest at a rate of 3.68% per annum and mature on March 17, 2021. Interest on the Series B Senior Notes is payable semi-annually beginning on September 17, 2014 and continuing thereafter on March 17 and September 17 of each year until maturity. The principal balance is due when the notes mature in 2021. The full net proceeds from the Series B Senior Notes were used for working capital and other general corporate purposes. At December 31, 2019 and 2018, the principal balance outstanding under the Series B Senior Notes was $40.0 million.

3.84% Senior Notes Due in 2022

On November 5, 2015, the Company issued and sold to the Purchasers a $60.0 million aggregate principal amount of its 3.84% Series C Senior Notes (the “Series C Senior Notes”) pursuant to the terms of the Note Purchase Agreement, as amended. The Series C Senior Notes are an unsecured obligation of the Company, bear interest at a rate of 3.84% per annum and mature on November 5, 2022. Interest on the Series C Senior Notes is payable semi-annually beginning on May 5, 2016 and continuing thereafter on November 5 and May 5 of each year until maturity. The principal balance is due when the notes mature in 2022. The full net proceeds from the Series C Senior Notes were used to reduce the outstanding balance on the Company’s revolving credit line. At December 31, 2019 and 2018, the principal balance outstanding under the Series C Senior Notes was $60.0 million.

Among other restrictions, the Note Purchase Agreement, under which the Series A Senior Notes, Series B Senior Notes and Series C Senior Notes were sold, contains financial covenants requiring the Company to not (all defined terms used below not otherwise defined herein have the meaning assigned to such terms in the Note Purchase Agreement):

•

Permit the Consolidated Fixed Charge Coverage Ratio of EBITDA to fixed charges as of the end of any fiscal quarter to be less than 2.50 to 1. At December 31, 2019, the actual ratio was 4.27 to 1.

•

Permit the Consolidated Leverage Ratio of funded debt to EBITDA at any time during any period of four consecutive quarters to be greater than 2.75 to 1. At December 31, 2019, the actual ratio was 1.24 to 1.

•

Permit Tangible Net Worth, calculated as of the last day of each fiscal quarter, to be less than the sum of (i) $229.0 million, plus (ii) 25% of net income for such fiscal quarter subsequent to December 31, 2010, plus (iii) 90% of the net cash proceeds from the issuance of the Company’s capital stock after December 31, 2010. At December 31, 2019, such sum was $388.1 million and the actual Tangible Net Worth of the Company was $598.5 million.

At December 31, 2019, the Company was in compliance with each of the aforementioned covenants. There are no anticipated trends that the Company is aware of that would indicate non-compliance with these covenants, though, significant deterioration in the Company’s financial performance could impact its ability to comply with these covenants.

Income Taxes

12 Months Ended

Dec. 31, 2019

Income Tax Disclosure [Abstract]

Income Taxes

NOTE 6. INCOME TAXES

Income before provision (benefit) for income taxes consisted of the following:

(in thousands)	Year Ended December 31,
	2019		2018			2017
U.S.	$	129,045	$	104,881		$	83,525
Foreign		80		(186	)		(73	)
	$	129,125	$	104,695		$	83,452

The provision (benefit) for income taxes consisted of the following:

(in thousands)	Year Ended December 31,
	2019			2018		2017
Current:
U.S. Federal	$	11,744		$	7,270	$	21,171
State		7,353			4,253		2,976
Foreign		1,616			1,731		2,016
		20,713			13,254		26,163
Deferred:
U.S. Federal		10,719			10,355		(103,518	)
State		895			1,637		6,948
Foreign		(8	)		43		(61	)
		11,606			12,035		(96,631	)
Total	$	32,319		$	25,289	$	(70,468	)

The reconciliation of the U.S. federal statutory tax rate to the Company’s effective tax rate is as follows:

	Year Ended December 31,
	2019			2018			2017
U.S. federal statutory rate		21.0	%		21.0	%		35.0	%
State taxes, net of federal benefit		5.0			5.0			4.1
State deferred tax rate change, net of federal benefit		0.1			0.7			0.5
Valuation allowance		0.0			(0.5	)		0.1
Share-based compensation		(1.6	)		(1.9	)		(1	)
Enactment of the Tax Cuts and Jobs Act		(0.1	)		(0.1	)		(123	)
Other		0.6			0.0			(0.2	)
		25.0	%		24.2	%		(84.4	)%

The following table shows the deferred income taxes related to the temporary differences between the tax bases of assets and liabilities and the respective amounts included in “Deferred income taxes, net” on the Company’s Consolidated Balance Sheets:

(in thousands)	December 31,
	2019		2018
Deferred tax liabilities:
Accelerated depreciation	$	221,627	$	208,539
Prepaid costs currently deductible		5,668		4,845
Other		5,011		4,703
Total deferred tax liabilities		232,306		218,087
Deferred tax assets:
Accrued costs not yet deductible		8,860		7,796
Allowance for doubtful accounts		486		486
Deferred revenues		2,512		1,774
Share-based compensation		2,178		1,367
Total deferred tax assets, net of valuation allowance of $0.2 million in 2019 and 2018		14,036		11,423
Deferred income taxes, net	$	218,270	$	206,664

The Tax Cuts and Jobs Act (the “Tax Act”) was enacted in December 2017. Among other provisions, the Tax Act reduced the U.S. federal corporate tax rate from 35% to 21% in 2018, required companies to pay a one-time transition tax on earnings of certain foreign subsidiaries that were previously tax deferred and created new taxes on certain foreign-source earnings. As of December 31, 2019, the Company completed its accounting for the tax effects of enactment of the Tax Act without any material adjustments to its previous estimates.

As of December 31, 2019 the Company did not have a deferred tax liability related to its foreign earnings because it did not have any specific plans to repatriate funds from its international subsidiaries. The Company may do so in the future if a dividend can be remitted with no material tax impact.

In December 2016, the Company decided to exit the Bangalore, India branch operations of its TRS-RenTelco electronics division. The wind down of operations in India began in 2017. As a result, a valuation allowance was recorded against the deferred tax assets that resulted primarily from accumulated net operating loss carry forwards in India that management estimated the benefit of which will not be realized. As of December 31, 2019, the Company’s foreign net operating losses for tax purposes were $0.6 million. If not realized, these carry forwards will begin to expire in 2023.

For income tax purposes, deductible compensation related to share-based awards is based on the value of the award when realized, which may be different than the compensation expense recognized by the company for financial statement purposes which is based on the award value on the date of grant. The difference between the value of the award upon grant, and the value of the award when ultimately realized, creates either additional tax expense or benefit. In 2019, 2018 and 2017 exercise of share-based awards by employees resulted in an excess tax benefit of $2.1 million, $2.0 million and $0.9 million, respectively.

The Company recognizes the financial statement benefit of a tax position only after determining that the relevant tax authority would more likely than not sustain the position following an audit. For tax positions meeting the more-likely-than-not threshold, the amount recognized in the financial statements is the largest benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement with the relevant tax authority. The Company evaluated all of its tax positions for which the statute of limitations remained open and determined there were no material unrecognized tax benefits as of December 31, 2019 and 2018. In addition, there have been no material changes in unrecognized benefits during 2019, 2018 and 2017.

The Company is subject to income taxes in the U.S. federal jurisdiction, and various states and foreign jurisdictions. Tax regulations within each jurisdiction are subject to interpretation of the related tax laws and regulations and require the application of significant judgment. With few exceptions, the Company is no longer subject to U.S. federal, state and local, or non-U.S. income tax examinations by tax authorities for the years before 2015.

Our income tax returns are subject to examination by federal, state and foreign tax authorities. There may be differing interpretations of tax laws and regulations, and as a result, disputes may arise with these tax authorities involving the timing and amount of deductions and allocation of income.

The Company recognizes interest and penalties related to unrecognized tax benefits in the provision (benefit) for income taxes in the accompanying Consolidated Statements of Income for all periods presented. Such interest and penalties were not significant for the years ended December 31, 2019, 2018 and 2017.

Benefit Plans

12 Months Ended

Dec. 31, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Benefit Plans

NOTE 7. BENEFIT PLANS

Stock Plans

The Company adopted the 2016 Stock Incentive Plan (the “2016 Plan”), effective June 8, 2016, under which 2,000,000 shares of the common stock of the Company, plus the number of shares that remain available for grants of awards under the Company's 2007 Stock Option Plan (the “2007 Plan”) and become available as a result of forfeiture, termination, or expiration of awards previously granted under the 2007 Plan, were reserved for the grant of equity awards to its employees, directors and consultants. The equity awards have a maximum term of 7 years at an exercise price of not less than 100% of the fair market value of the Company's common stock on the date the equity award is granted. The 2016 Plan replaced the 2007 Plan.

The 2016 Plan provides for the grant of awards in the form of stock options, stock appreciation rights, restricted stock units (“RSUs”), the vesting of which may be performance-based or service-based, and other rights and benefits. Each RSU issued reduces the number of shares of the Company’s common stock available for grant under the 2016 Plan by two shares. There were no modifications to the 2016 Plan and no awards classified as liabilities in the year ended December 31, 2019.

For the years ended December 31, 2019, 2018 and 2017, the share-based compensation expense was $5.9 million, $4.1 million and $3.2 million, respectively, before provision for income taxes. The Company recorded a tax benefit of approximately $1.6 million, $1.1 million and $1.3 million, respectively, related to the aforementioned share-based compensation expenses. There was no capitalized share-based compensation expense in the years ended December 31, 2019, 2018 and 2017.

Stock Options

As of December 31, 2019, a cumulative total of 8,458,600 shares subject to options have been granted with exercise prices ranging from $3.47 to $40.37. Of these, options have been exercised for the purchase of 6,214,548 shares, while options for 1,663,912 shares have been terminated, and options for 580,140 shares with exercise prices ranging from $24.60 to $40.37 remained outstanding under the stock plans. These options vest over five years and expire seven years after grant. To date, no options have been issued to

any of the Company’s non-employee advisors. As of December 31, 2019, 1,708,914 shares remained available for issuance of awards under the stock plans.

A summary of the Company’s option activity and related information for the three years ended December 31, 2019 is as follows:

	Number of options			Weighted- average price		Weighted- average remaining contractual term (in years)		Aggregate intrinsic value (in millions)
Balance at December 31, 2016		1,584,435		$	28.14
Options granted		299,600			34.66
Options exercised		(398,275	)		28.94
Options cancelled/forfeited/expired		(276,900	)		28.04
Balance at December 31, 2017		1,208,860			28.14
Options granted		—			—
Options exercised		(332,810	)		29.49
Options cancelled/forfeited/expired		(30,450	)		28.27
Balance at December 31, 2018		845,600			28.14
Options granted		—			—
Options exercised		(260,860	)		29.55
Options cancelled/forfeited/expired		(4,600	)		30.59
Balance at December 31, 2019		580,140		$	29.57		3.31	$	27.2
Exercisable at December 31, 2019		289,350		$	29.35		3.00	$	13.6
Expected to vest after December 31, 2019		289,003		$	29.80		3.61	$	13.5

The intrinsic value of stock options at any point in time is calculated as the difference between the exercise price of the underlying awards and the quoted price of the Company’s common stock. The aggregate intrinsic value of options exercised and sold under the Company’s stock option plans was $9.1 million, $9.0 million and $5.0 million for the years ended December 31, 2019, 2018 and 2017, respectively, determined as of the date of option exercise. As of December 31, 2019, there was approximately $1.4 million of total unrecognized compensation cost related to unvested share-based compensation option arrangements granted under the Company’s stock plans, which is expected to be recognized over a weighted-average period of 1.1 years.

The following table indicates the options outstanding and options exercisable by exercise price with the weighted-average remaining contractual life for the options outstanding and the weighted-average exercise price at December 31, 2019:

	Options Outstanding						Options Exercisable
Exercise price	Number outstanding at December 31, 2019		Weighted-average remaining contractual life (Years)		Weighted-average grant date value		Number exercisable at December 31, 2019		Weighted-average grant date value
$20 – 25		256,640		3.17	$	24.60		128,440	$	24.60
$25 – 30		6,150		3.13	$	25.13		1,120	$	25.14
$30 – 35		306,810		3.40	$	33.48		155,710	$	33.04
$35 – 40		6,800		4.00	$	39.19		4,080	$	39.19
$40 – 45		3,740		4.67	$	40.37		—	$	—
$20 – 45		580,140		3.31	$	29.57		289,350	$	29.35

The Company utilizes the Black-Scholes option-pricing model to estimate the fair value of share-based compensation at the date of grant, which requires the use of accounting judgment and financial estimates, including estimates of the expected term option holders will retain their vested stock options before exercising them, the estimated volatility of the Company’s stock price over the expected term and the expected number of options that will be forfeited prior to the completion of their vesting requirements. Application of alternative assumptions could produce significantly different estimates of the fair value of share-based compensation amounts recognized in the Consolidated Statements of Income.

The fair value of each option granted was estimated on the date of grant using the Black-Scholes option-pricing model using the following weighted-average assumptions:

	Year Ended December 31,
	2019		2018		2017
Expected term (in years)		—		—		5.0
Expected volatility		—		—		26.1	%
Expected dividend yields		—		—		3.0	%
Risk-free interest rates		—		—		2.0	%

The Company monitors option exercise behavior to determine the appropriate homogenous groups for estimation purposes. The Company’s option activity is separated into two categories: directors and employees. The expected term of the options represents the estimated period of time until exercise and is based on historical experience, giving consideration to the option terms, vesting schedules and expectations of future behavior. Expected stock volatility was based on historical stock price volatility of the Company and the risk-free interest rates were based on U.S. Treasury yields in effect on the date of the option grant for the estimated period the options will be outstanding. The expected dividend yield was based upon the current dividend annualized as a percentage of the grant exercise price.

No options were granted in 2019 and 2018. The weighted average grant date fair value per share was $6.28 during the year ended December 31, 2017.

Restricted Stock Units

The following table summarizes the activity of the Company’s RSUs, which includes service-based and performance-based awards, for the three years ended December 31, 2019:

				Weighted-		Aggregate
				average		intrinsic
	Number			grant date		value
	of shares			fair value		(in millions)
Balance at December 31, 2016		125,240			30.66
RSUs granted		70,960			34.53
RSUs vested		(36,336	)		26.99
RSUs cancelled/forfeited/expired		(66,200	)		32.63
Balance at December 31, 2017		93,664			33.62
RSUs granted		97,260			49.47
RSUs vested		(30,214	)		33.16
RSUs cancelled/forfeited/expired		(21,200	)		33.88
Balance at December 31, 2018		139,510			44.73
RSUs granted		83,440			59.98
RSUs vested		(25,862	)		48.31
RSUs cancelled/forfeited/expired		(840	)		59.84
Balance at December 31, 2019		196,248		$	50.68	$	15.0

Performance-based RSUs issued prior to 2018 vest over five years, with 60% of the shares immediately vesting after three years when the performance criteria has been determined to have been met and 20% of the remaining shares vesting annually at the anniversary of the performance determination date, subject to continuous employment of the participant. The 2018 and 2019 performance-based RSU grants vest after three years with 100% of the shares vesting immediately when performance criteria has been determined to have been met. There were 200,839 performance-based RSUs expected to vest as of December 31, 2019. Service-based RSUs issued to the Company’s directors generally vest over twelve to fourteen months. Service–based RSUs issued to the Company’s management vest over three years. There were 81,984 service-based RSUs expected to vest as of December 31, 2019. No forfeitures are currently expected. The total fair value of RSUs that vested during the years ended December 31, 2019, 2018 and 2017 based on the weighted average grant date values was $1.2 million, $1.0 million and $1.0 million, respectively.

Share-based compensation expense for RSUs for the year ended December 31, 2019, 2018 and 2017 was $4.7 million, $2.6 million and $1.4, respectively. As of December 31, 2019, the total unrecognized compensation expense related to unvested RSUs was $6.9 million and is expected to be recognized over a weighted-average period of 2.1 years.

Employee Stock Ownership and 401(k) Plans

The McGrath RentCorp Employee Stock Ownership and 401(k) Plan (the “KSOP”) provides that each participant may annually contribute an elected percentage of his or her salary, not to exceed the statutory limit. Each employee who has at least three months of service with the Company and is 21 years or older, is eligible to participate in the KSOP. The Company, at its discretion, may make matching contributions. Contributions are expensed in the year approved by the Board of Directors. Dividends on the Company’s stock held by the KSOP are treated as ordinary dividends and, in accordance with existing tax laws, are deducted by the Company in the year paid. For the year ended December 31, 2019 dividends deducted by the Company were $0.4 million, which resulted in a tax benefit of approximately $0.1 million in 2019.

At December 31, 2019, the KSOP held 241,956 shares, or 1% of the Company’s total common shares outstanding. These shares are included in basic and diluted earnings per share calculations.

Shareholders' Equity

12 Months Ended

Dec. 31, 2019

Equity [Abstract]

Shareholders' Equity

NOTE 8. SHAREHOLDERS’ EQUITY

The Company has in the past made purchases of shares of its common stock from time to time in over-the-counter market (NASDAQ) transactions, through privately negotiated, large block transactions and through a share repurchase plan, in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934. In August 2015, the Company’s Board of Directors authorized the Company to repurchase 2,000,000 shares of the Company's outstanding common stock. The amount and time of the specific repurchases are subject to prevailing market conditions, applicable legal requirements and other factors, including management’s discretion. All shares repurchased by the Company are canceled and returned to the status of authorized but unissued shares of common stock. There can be no assurance that any authorized shares will be repurchased and the repurchase program may be modified, extended or terminated by the board of directors at any time. There were no repurchases of common stock during the twelve months ended December 31, 2019 and 2018. As of December 31, 2019, 1,592,026 shares remain authorized for repurchase under this authorization.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2019

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

NOTE 9. COMMITMENTS AND CONTINGENCIES

The Company leases certain facilities under various operating leases. Most of the lease agreements provide the Company with the option of renewing its lease at the end of the lease term, at the fair rental value. In most cases, management expects that in the normal course of business, facility leases will be renewed or replaced by other leases. Minimum payments under these leases, exclusive of property taxes and insurance, are as follows:

(in thousands)
Year Ended December 31,
2020	$	2,732
2021		2,370
2022		1,805
2023		1,290
2024		1,005
Thereafter		293
	$	9,495

Facility rent expense was $3.9 million in 2019 and $3.5 million in 2018 and 2017.

The Company is involved in various lawsuits and routine claims arising out of the normal course of its business. The Company maintains insurance coverage for its operations and employees with appropriate aggregate, per occurrence and deductible limits as the Company reasonably determines necessary or prudent with current operations and historical experience. The major policies include coverage for property, general liability, auto, directors and officers, health, and workers’ compensation insurances. The Company records a provision for a liability when it believes that it is both probable that a liability has been incurred and the amount can be reasonably estimated. Significant judgment is required to determine both probability and the estimated amount. The Company reviews these provisions at least quarterly and adjusts these provisions to reflect the impact of negotiations, settlements, rulings, advice of legal counsel, and updated information. Litigation is inherently unpredictable and is subject to significant uncertainties, some of which are beyond the Company’s control. In the opinion of management, there was not at least a reasonable possibility that the ultimate amount of liability not covered by insurance, if any, under any pending litigation and claims, individually or in the aggregate, will have a material adverse effect on the financial position or operating results of the Company.

The Company’s health plans is self-funded high deductible plans with annual stop-loss insurance of $200,000 per claim. Beginning in 2019, the Company’s workers compensation insurance is underwritten by an insurance company with no stop-loss value and $350,000 for prior claim years. Insurance providers are responsible for making claim payments that exceed these amounts on an individual claim basis. In addition, the Company has stop loss insurance that pays for claim payments made during a twelve month coverage period that exceeds certain specified thresholds in the aggregate. The Company records an expense when health and workers compensation claim payments are made and accrues for the portion of claims incurred, but not yet paid at period end. The Company makes these accruals based upon a combination of historical claim payments, loss development experience and actuarial estimates. A high degree of judgment is required in developing the underlying assumptions and the resulting amounts to be accrued. In addition, our assumptions will change as the Company’s loss experience develops. All of these factors have the potential for impacting the amounts previously accrued and the Company may be required to increase or decrease the amounts previously accrued. At December 31, 2019 and 2018, accruals for the Company’s health and workers’ compensation high deductible plans were $2.8 million and $3.0 million, respectively.

Intangible Assets

12 Months Ended

Dec. 31, 2019

Goodwill And Intangible Assets Disclosure [Abstract]

Intangible Assets

NOTE 10. INTANGIBLE ASSETS

Intangible assets consist of the following:

(dollar amounts in thousands)	Estimated useful life in years		December 31, 2019			December 31, 2018
Trade name	Indefinite		$	5,871		$	5,871
Customer relationships		11		10,644			9,849
Non-compete agreements		5		157			—
				16,672			15,720
Less accumulated amortization				(9,338	)		(8,466	)
			$	7,334		$	7,254

Intangible assets with finite useful lives are amortized over their respective useful lives. Amortization expense in each of the years ended December 31, 2019, 2018 and 2017 was $0.9 million. Based on the carrying values at December 31, 2019 and assuming no subsequent impairment of the underlying assets, the annual amortization is expected to be $0.2 million in 2020 and $0.2 million in 2021 through 2026.

Acquisition

12 Months Ended

Dec. 31, 2019

Business Combinations [Abstract]

Acquisition

NOTE 11. ACQUISITION

On August 15, 2019, the Company completed the purchase of the container rental business of ATP Containers LLC, dba TuffBox Container (“TuffBox”) for $7.8 million. The Company accounted for this transaction as a business combination and the initial assessment of the fair value of the purchased assets was allocated primarily to rental equipment totaling $5.5 million and intangible assets totaling $1.3 million, which included $0.4 million allocated to goodwill. The goodwill represents the future economic benefits to be derived from the geographic market expansion of the Company’s portable storage division. The goodwill was recorded in the Mobile Modular segment and is fully deductible for income tax purposes.

The TuffBox operating results are included in the Mobile Modular segment results since the date of acquisition. Supplemental pro forma prior year information has not been provided as the historical financial results of TuffBox were not significant. Incremental transaction costs associated with the acquisition were not significant.

Related Party Transactions

12 Months Ended

Dec. 31, 2019

Related Party Transactions

NOTE 12. RELATED PARTY TRANSACTIONS

There were no related party transactions in the years ended December 31, 2019 and 2018, or amounts owed to related parties at such dates.

Segment Reporting

12 Months Ended

Dec. 31, 2019

Segment Reporting [Abstract]

Segment Reporting

NOTE 13. SEGMENT REPORTING

FASB guidelines establish annual and interim reporting standards for an enterprise’s operating segments and related disclosures about its products, services, geographic areas and major customers. In accordance with these guidelines the Company’s four reportable segments are Mobile Modular, TRS-RenTelco, Adler Tanks and Enviroplex. Management focuses on several key measures to evaluate and assess each segment’s performance including rental revenue growth, gross margin, and income before provision for income taxes. Excluding interest expense, allocations of revenue and expense not directly associated with one of these segments are generally allocated to Mobile Modular, TRS-RenTelco and Adler Tanks, based on their pro-rata share of direct revenues. Interest expense is allocated amongst Mobile Modular, TRS-RenTelco and Adler Tanks based on their pro-rata share of average rental equipment at cost, goodwill, intangible assets, accounts receivable, deferred income and customer security deposits. The Company does not report total assets by business segment. Summarized financial information for the years ended December 31, 2019, 2018 and 2017, for the Company’s reportable segments is shown in the following tables:

(dollar amounts in thousands)	Mobile Modular			TRS- RenTelco			Adler Tanks			Enviroplex ¹			Consolidated
Year Ended December 31,
2019
Rental revenues	$	182,316		$	103,704		$	67,869		$	—		$	353,889
Rental related services revenues		69,395			3,260			28,383		—				101,038
Sales and other revenues		49,299			24,519			1,671			39,814			115,303
Total revenues		301,010			131,483			97,923			39,814			570,230
Depreciation of rental equipment		22,071			41,948			16,372		—				80,391
Gross profit		143,618			60,748			47,014			14,785			266,165
Selling and administrative expenses		65,699			24,645			29,321			5,128			124,793
Income from operations		77,919			36,103			17,693			9,657			141,372
Interest expense (income) allocation		7,946			1,970			3,436			(1,021	)		12,331
Income before provision for income taxes		69,973			34,217			14,257			10,678			129,125
Rental equipment acquisitions		75,433			89,759			4,826		—				170,018
Accounts receivable, net (period end)		83,182			23,788			17,281			3,848			128,099
Rental equipment, at cost (period end)		868,807			335,343			316,261		—				1,520,411
Rental equipment, net book value (period end)		610,048			172,413			185,039		—				967,500
Utilization (period end) ²		79.1	%		64.5	%		48.4	%
Average utilization ²		79.2	%		66.2	%		54.7	%

Segment Data (Continued) (dollar amounts in thousands)	Mobile Modular			TRS- RenTelco			Adler Tanks			Enviroplex 1		Consolidated
Year Ended December 31,
2018
Rental revenues	$	159,136		$	89,937		$	69,701		$	—	$	318,774
Rental related services revenues		54,696			3,300			24,911		—			82,907
Sales and other revenues		40,742			25,420			1,441			29,046		96,649
Total revenues		254,574			118,657			96,053			29,046		498,330
Depreciation of rental equipment		21,200			36,011			15,928		—			73,139
Gross profit		120,750			54,773			48,055			9,673		233,251
Selling and administrative expenses		58,017			22,823			30,026			4,904		115,770
Income from operations		62,733			31,950			18,029			4,769		117,481
Interest expense (income) allocation		(7,132	)		(2,696	)		(3,252	)		783		(12,297	)
Income before benefit for income taxes		55,601			28,765			14,777			5,552		104,695
Rental equipment acquisitions		63,374			65,467			5,257		—			134,098
Accounts receivable, net (period end)		72,295			20,732			19,992			7,997		121,016
Rental equipment, at cost (period end)		817,375			285,052			313,573		—			1,416,000
Rental equipment, net book value (period end)		572,032			131,450			197,533		—			901,015
Utilization (period end) 2		79.3	%		62.1	%		56.4	%
Average utilization 2		78.2	%		62.7	%		59.9	%

2017
Rental revenues	$	142,584		$	82,812		$	64,021		$	—	$	289,417
Rental related services revenues		50,448			2,858			24,762		—			78,068
Sales and other revenues		38,234			22,374			2,572			31,369		94,549
Total revenues		231,266			108,044			91,355			31,369		462,034
Depreciation of rental equipment		21,247			32,891			15,770		—			69,908
Gross profit		103,935			50,289			43,218			8,903		206,345
Selling and administrative expenses		55,583			22,171			29,542			4,309		111,605
Income from operations		48,352			28,118			13,676			4,594		94,740
Interest expense (income) allocation		(6,671	)		(2,320	)		(3,071	)		440		(11,622	)
Income before provision for income taxes		41,681			26,132			10,605			5,034		83,452
Rental equipment acquisitions		34,526			58,781			4,800		—			98,107
Accounts receivable, net (period end)		59,274			19,581			18,663			8,354		105,872
Rental equipment, at cost (period end)		775,400			262,325			309,808		—			1,347,533
Rental equipment, net book value (period end)		543,857			109,482			208,981		—			862,320
Utilization (period end) 2		77.8	%		61.7	%		57.5	%
Average utilization 2		76.8	%		62.9	%		56.0	%

1	Gross Enviroplex sales revenues were $39,814, $30,407 and $31,369 in 2019, 2018 and 2017, respectively. There were $1,361 inter-segment sales to Mobile Modular in 2018, which have been eliminated in consolidation. There were no inter-segment sales in 2019 and 2017.

2	Utilization is calculated each month by dividing the cost of rental equipment on rent by the total cost of rental equipment excluding new equipment inventory and accessory equipment. The average utilization for the period is calculated using the average costs of rental equipment.

No single customer accounted for more than 10% of total revenues during 2019, 2018 and 2017. Revenue from foreign country customers accounted for 5%, 4% and 4% of the Company’s revenues for the same periods, respectively.

Quarterly Financial Information

12 Months Ended

Dec. 31, 2019

Quarterly Financial Information Disclosure [Abstract]

Quarterly Financial Information

NOTE 14. QUARTERLY FINANCIAL INFORMATION (unaudited)

Quarterly financial information for each of the two years ended December 31, 2019 is summarized below:

(in thousands, except per share amounts)	2019
	First		Second		Third		Fourth		Year
Operations Data
Rental revenues	$	82,696	$	88,105	$	90,857	$	92,231	$	353,889
Total revenues		122,008		127,439		173,562		147,221		570,230
Gross profit		57,005		59,881		78,282		70,997		266,165
Income from operations		27,310		29,066		46,748		38,248		141,372
Income before provision for income taxes		24,251		25,965		43,455		35,454		129,125
Net income		18,449		19,488		32,468		26,401		96,806
Earnings per share:
Basic	$	0.76	$	0.80	$	1.34	$	1.09	$	3.99
Diluted	$	0.75	$	0.79	$	1.32	$	1.07	$	3.93
Dividends declared per share	$	0.375	$	0.375	$	0.375	$	0.375	$	1.50
Shares used in per share calculations:
Basic		24,195		24,246		24,268		24,290		24,250
Diluted		24,540		24,579		24,632		24,697		24,623
Balance Sheet Data
Rental equipment, net	$	912,878	$	943,152	$	958,610	$	967,500	$	967,500
Total assets		1,239,633		1,280,249		1,306,223		1,309,875		1,309,875
Notes payable		289,464		301,878		301,469		293,431		293,431
Shareholders’ equity		580,643		592,309		616,715		634,036		634,036

	2018
	First		Second		Third		Fourth		Year
Operations Data
Rental revenues	$	74,261	$	77,267	$	82,155	$	85,091	$	318,774
Total revenues		105,085		116,983		143,147		133,115		498,330
Gross profit		50,170		53,928		64,050		65,103		233,251
Income from operations		22,042		24,449		35,824		35,166		117,481
Income before provision for income taxes		19,018		21,106		32,553		32,018		104,695
Net income		14,466		15,912		24,779		24,249		79,406
Earnings per share:
Basic	$	0.60	$	0.66	$	1.03	$	1.00	$	3.29
Diluted	$	0.59	$	0.65	$	1.01	$	0.99	$	3.24
Dividends declared per share	$	0.34	$	0.34	$	0.34	$	0.34	$	1.36
Shares used in per share calculations:
Basic		24,067		24,145		24,172		24,179		24,141
Diluted		24,478		24,584		24,563		24,514		24,540
Balance Sheet Data
Rental equipment, net	$	865,338	$	876,522	$	888,607	$	901,015	$	901,015
Total assets		1,148,858		1,180,209		1,201,799		1,217,316		1,217,316
Notes payable		300,595		314,860		309,006		298,564		298,564
Shareholders’ equity		530,284		537,195		554,547		571,535		571,535

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2019

Principles of Consolidation

Organization

The consolidated financial statements include the accounts of McGrath RentCorp and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.

Revenue Recognition

Other revenue is recognized when earned and primarily includes interest income on sales-type leases, rental income on facility leases and certain logistics services.

Sales taxes charged to customers are reported on a net basis and are excluded from revenues and expenses.

Depreciation of Rental Equipment

The estimated useful lives and residual values of the Company’s rental equipment used for financial reporting purposes are as follows:

Relocatable modular buildings		18 years, 50% residual value
Relocatable modular accessories		3 to 18 years, no residual value
Blast resistant modules		20 years, no residual value
Portable storage containers		25 years, 62.5% residual value
Electronic test equipment and accessories		1 to 8 years, no residual value
Liquid and solid containment tanks and boxes and accessories		3 to 20 years, no residual value

Costs of Rental Related Services

Impairment of Long-Lived Assets

Other Direct Costs of Rental Operations

Cost of Sales

Cost of sales in the Consolidated Statements of Income includes the carrying value of the equipment sold and all direct costs associated with the sale.

Warranty Reserves

Property, Plant and Equipment

Property, plant and equipment consist of the following:

(dollar amounts in thousands)	Estimated useful life		December 31,
	in years		2019			2018
Land	Indefinite		$	54,423		$	50,689
Land improvements	20 – 50			52,325			50,064
Buildings		30		29,848			29,359
Furniture, office and computer equipment	3 – 10			36,610			33,081
Vehicles and machinery	5 – 25			41,877			38,199
				215,083			201,392
Less accumulated depreciation				(84,308	)		(77,118	)
				130,775			124,274
Construction in progress				272			2,625
			$	131,047		$	126,899

Capitalized Software Costs

Advertising Costs

Advertising costs are expensed as incurred. Total advertising expenses were $3.6 million, $3.2 million and $2.9 million for the years ended December 31, 2019, 2018 and 2017.

Income Taxes

Goodwill and Intangible Assets

Earnings Per Share

(in thousands)	Year Ended December 31,
	2019		2018		2017
Weighted-average common stock for calculating basic earnings per share		24,250		24,141		23,999
Effect of potentially dilutive securities from equity-based compensation		373		399		270
Weighted-average common stock for calculating diluted earnings per share		24,623		24,540		24,269

Accounts Receivable and Concentration of Credit Risk

(in thousands)	2019			2018
Beginning balance, January 1	$	1,883		$	1,920
Provision for doubtful accounts		1,013			581
Write-offs, net of recoveries		(1,013	)		(618	)
Ending balance, December 31	$	1,883		$	1,883

Fair Value of Financial Instruments

Foreign Currency Transactions and Translation

Share-Based Compensation

Use of Estimates

identifiable definite lived intangible assets carrying value, the various assets’ useful lives and residual values, and the allowance for doubtful accounts.

Income Tax Position

Segment Reporting

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2019

Estimated Useful Lives and Residual Values of Company's Rental Equipment

The estimated useful lives and residual values of the Company’s rental equipment used for financial reporting purposes are as follows:

Relocatable modular buildings		18 years, 50% residual value
Relocatable modular accessories		3 to 18 years, no residual value
Blast resistant modules		20 years, no residual value
Portable storage containers		25 years, 62.5% residual value
Electronic test equipment and accessories		1 to 8 years, no residual value
Liquid and solid containment tanks and boxes and accessories		3 to 20 years, no residual value

Property, Plant and Equipment

Property, plant and equipment consist of the following:

(dollar amounts in thousands)	Estimated useful life		December 31,
	in years		2019			2018
Land	Indefinite		$	54,423		$	50,689
Land improvements	20 – 50			52,325			50,064
Buildings		30		29,848			29,359
Furniture, office and computer equipment	3 – 10			36,610			33,081
Vehicles and machinery	5 – 25			41,877			38,199
				215,083			201,392
Less accumulated depreciation				(84,308	)		(77,118	)
				130,775			124,274
Construction in progress				272			2,625
			$	131,047		$	126,899

Weighted-Average Common Stock Used to Calculate Basic and Diluted Earnings per Share

The table below presents the weighted-average common stock used to calculate basic and diluted earnings per share:

(in thousands)	Year Ended December 31,
	2019		2018		2017
Weighted-average common stock for calculating basic earnings per share		24,250		24,141		23,999
Effect of potentially dilutive securities from equity-based compensation		373		399		270
Weighted-average common stock for calculating diluted earnings per share		24,623		24,540		24,269

Summary of Allowance for Doubtful Accounts Activity

The allowance for doubtful accounts activity was as follows:

(in thousands)	2019			2018
Beginning balance, January 1	$	1,883		$	1,920
Provision for doubtful accounts		1,013			581
Write-offs, net of recoveries		(1,013	)		(618	)
Ending balance, December 31	$	1,883		$	1,883

Implemented Accounting Pronouncements (Tables)

12 Months Ended

Dec. 31, 2019

Accounting Changes And Error Corrections [Abstract]

Summary of Supplemental Cash flow Information Related to Leases

Supplemental cash flow information related to leases was as follows:

(in thousands)	Year Ended
	December 31, 2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	3,568

Right of use assets obtained in exchange for lease obligations:
Operating leases	$	2,728

Summary of Maturities of Operating Lease Liabilities

As of December 31, 2019, maturities of operating lease liabilities were as follows:

(in thousands)
Year ended December 31,
2020	$	3,350
2021		2,794
2022		1,958
2023		1,458
2024		915
Thereafter		293
Total lease payments		10,768
Less imputed interest		(823	)
	$	9,945

Summary of Maturities of Operating Lease Payments

As of December 31, 2019, maturities of operating lease payments to be received in 2020 and thereafter were as follows:

(in thousands)
Year Ended December 31,
2020	$	92,821
2021		30,926
2022		8,922
2023		2,145
2024		877
Thereafter		37
	$	135,728

Minimum Lease Payments Receivable and Net Investment Included in Accounts Receivable for Leases

The minimum lease payments receivable and the net investment are included in Accounts receivable on the Company’s Consolidated Balance Sheet for such leases, which were as follows:

(in thousands)	December 31, 2019
Gross minimum lease payments receivable	$	3,218
Less – unearned interest		(289	)
Net investment in finance lease receivables	$	2,929

Future Minimum Lease Payments under Non-Cancelable Finance Leases

As of December 31, 2019, the future minimum lease payments under non-cancelable finance leases to be received in 2020 and thereafter were as follows:

(in thousands)
Year Ended December 31,
2020	$	2,345
2021		629
2022		184
2023		50
2024		10
Thereafter		—
Total minimum future lease payments to be received	$	3,218

Revenue Recognition (Tables)

12 Months Ended

Dec. 31, 2019

Disaggregation Of Revenue [Abstract]

Summary of Disaggregates the Company's Revenue by Lease and Non Lease

(in thousands)	Mobile Modular			TRS- RenTelco		Adler Tanks			Enviroplex		Consolidated
Year Ended December 31,
2019
Leasing	$	234,032		$	108,044	$	68,917		$	—	$	410,993
Non-lease:
Rental related services		18,964			2,599		27,634			—		49,197
Sales		47,045			18,995		1,266			39,814		107,120
Other		969			1,845		106			—		2,920
Total non-lease		66,978			23,439		29,006			39,814		159,237
Total revenues	$	301,010		$	131,483	$	97,923		$	39,814	$	570,230

2018
Leasing	$	200,214		$	94,345	$	70,653		$	—	$	365,212
Non-lease:
Rental related services		14,870			2,607		24,276			—		41,753
Sales		39,467			19,895		1,044			29,046		89,452
Other		23			1,810		80			—		1,913
Total non-lease		54,360			24,312		25,400			29,046		133,118
Total revenues	$	254,574		$	118,657	$	96,053		$	29,046	$	498,330

2017
Leasing	$	180,612		$	85,930	$	64,676		$	—	$	331,218
Non-lease:
Rental related services		13,331			2,358		24,322			—		40,011
Sales		37,434			18,137		2,362			31,369		89,302
Other		(111	)		1,619		(5	)		—		1,503
Total non-lease		50,654			22,114		26,679			31,369		130,816
Total revenues	$	231,266		$	108,044	$	91,355		$	31,369	$	462,034

Notes Payable (Tables)

12 Months Ended

Dec. 31, 2019

Debt Disclosure [Abstract]

Components of Notes Payable

Notes payable consists of the following:

(in thousands)	December 31,
	2019			2018
Unsecured revolving lines of credit	$	193,459		$	198,603
3.68% Series B senior notes due in 2021		40,000			40,000
3.84% Series C senior notes due in 2022		60,000			60,000
		293,459			298,603
Unamortized debt issuance cost		(28	)		(39	)
	$	293,431		$	298,564

Schedule of Future Minimum Payments under Unsecured Revolving Lines of Credit and 4.03% Senior Notes, 3.68% Senior Notes and 3.84% Senior Notes

As of December 31, 2019, the future minimum payments under the unsecured revolving lines of credit, 3.68% Series B senior notes due in 2021 and 3.84% Series C senior notes due in 2022 are as follows:

(in thousands)
Year Ended December 31,
2020	$	—
2021		233,459
2022		60,000
	$	293,459

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Income Tax Disclosure [Abstract]

Schedule of Income Before Provision (Benefit) for Income Taxes

Income before provision (benefit) for income taxes consisted of the following:

(in thousands)	Year Ended December 31,
	2019		2018			2017
U.S.	$	129,045	$	104,881		$	83,525
Foreign		80		(186	)		(73	)
	$	129,125	$	104,695		$	83,452

Provision (Benefit) for Income Taxes

The provision (benefit) for income taxes consisted of the following:

(in thousands)	Year Ended December 31,
	2019			2018		2017
Current:
U.S. Federal	$	11,744		$	7,270	$	21,171
State		7,353			4,253		2,976
Foreign		1,616			1,731		2,016
		20,713			13,254		26,163
Deferred:
U.S. Federal		10,719			10,355		(103,518	)
State		895			1,637		6,948
Foreign		(8	)		43		(61	)
		11,606			12,035		(96,631	)
Total	$	32,319		$	25,289	$	(70,468	)

Reconciliation of U.S. Federal Statutory Tax Rate to Company's Effective Tax Rate

The reconciliation of the U.S. federal statutory tax rate to the Company’s effective tax rate is as follows:

	Year Ended December 31,
	2019			2018			2017
U.S. federal statutory rate		21.0	%		21.0	%		35.0	%
State taxes, net of federal benefit		5.0			5.0			4.1
State deferred tax rate change, net of federal benefit		0.1			0.7			0.5
Valuation allowance		0.0			(0.5	)		0.1
Share-based compensation		(1.6	)		(1.9	)		(1	)
Enactment of the Tax Cuts and Jobs Act		(0.1	)		(0.1	)		(123	)
Other		0.6			0.0			(0.2	)
		25.0	%		24.2	%		(84.4	)%

Deferred Income Taxes Related to Temporary Differences between Tax Bases of Assets and Liabilities

(in thousands)	December 31,
	2019		2018
Deferred tax liabilities:
Accelerated depreciation	$	221,627	$	208,539
Prepaid costs currently deductible		5,668		4,845
Other		5,011		4,703
Total deferred tax liabilities		232,306		218,087
Deferred tax assets:
Accrued costs not yet deductible		8,860		7,796
Allowance for doubtful accounts		486		486
Deferred revenues		2,512		1,774
Share-based compensation		2,178		1,367
Total deferred tax assets, net of valuation allowance of $0.2 million in 2019 and 2018		14,036		11,423
Deferred income taxes, net	$	218,270	$	206,664

Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Company's Option Activity

A summary of the Company’s option activity and related information for the three years ended December 31, 2019 is as follows:

	Number of options			Weighted- average price		Weighted- average remaining contractual term (in years)		Aggregate intrinsic value (in millions)
Balance at December 31, 2016		1,584,435		$	28.14
Options granted		299,600			34.66
Options exercised		(398,275	)		28.94
Options cancelled/forfeited/expired		(276,900	)		28.04
Balance at December 31, 2017		1,208,860			28.14
Options granted		—			—
Options exercised		(332,810	)		29.49
Options cancelled/forfeited/expired		(30,450	)		28.27
Balance at December 31, 2018		845,600			28.14
Options granted		—			—
Options exercised		(260,860	)		29.55
Options cancelled/forfeited/expired		(4,600	)		30.59
Balance at December 31, 2019		580,140		$	29.57		3.31	$	27.2
Exercisable at December 31, 2019		289,350		$	29.35		3.00	$	13.6
Expected to vest after December 31, 2019		289,003		$	29.80		3.61	$	13.5

Options Outstanding and Options Exercisable by Exercise Price with Weighted-Average Remaining Contractual Life for Options Outstanding and Weighted-Average Exercise Price

	Options Outstanding						Options Exercisable
Exercise price	Number outstanding at December 31, 2019		Weighted-average remaining contractual life (Years)		Weighted-average grant date value		Number exercisable at December 31, 2019		Weighted-average grant date value
$20 – 25		256,640		3.17	$	24.60		128,440	$	24.60
$25 – 30		6,150		3.13	$	25.13		1,120	$	25.14
$30 – 35		306,810		3.40	$	33.48		155,710	$	33.04
$35 – 40		6,800		4.00	$	39.19		4,080	$	39.19
$40 – 45		3,740		4.67	$	40.37		—	$	—
$20 – 45		580,140		3.31	$	29.57		289,350	$	29.35

Schedule of Weighted-Average Assumptions Used to Determine Fair Value of Option Granted

The fair value of each option granted was estimated on the date of grant using the Black-Scholes option-pricing model using the following weighted-average assumptions:

	Year Ended December 31,
	2019		2018		2017
Expected term (in years)		—		—		5.0
Expected volatility		—		—		26.1	%
Expected dividend yields		—		—		3.0	%
Risk-free interest rates		—		—		2.0	%

Summary of Company's Restricted Stock Units Activity

The following table summarizes the activity of the Company’s RSUs, which includes service-based and performance-based awards, for the three years ended December 31, 2019:

				Weighted-		Aggregate
				average		intrinsic
	Number			grant date		value
	of shares			fair value		(in millions)
Balance at December 31, 2016		125,240			30.66
RSUs granted		70,960			34.53
RSUs vested		(36,336	)		26.99
RSUs cancelled/forfeited/expired		(66,200	)		32.63
Balance at December 31, 2017		93,664			33.62
RSUs granted		97,260			49.47
RSUs vested		(30,214	)		33.16
RSUs cancelled/forfeited/expired		(21,200	)		33.88
Balance at December 31, 2018		139,510			44.73
RSUs granted		83,440			59.98
RSUs vested		(25,862	)		48.31
RSUs cancelled/forfeited/expired		(840	)		59.84
Balance at December 31, 2019		196,248		$	50.68	$	15.0

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2019

Commitments And Contingencies Disclosure [Abstract]

Minimum Payments under Leases, Exclusive of Property Taxes and Insurance

Minimum payments under these leases, exclusive of property taxes and insurance, are as follows:

(in thousands)
Year Ended December 31,
2020	$	2,732
2021		2,370
2022		1,805
2023		1,290
2024		1,005
Thereafter		293
	$	9,495

Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2019

Goodwill And Intangible Assets Disclosure [Abstract]

Summary of Intangible Assets

Intangible assets consist of the following:

(dollar amounts in thousands)	Estimated useful life in years		December 31, 2019			December 31, 2018
Trade name	Indefinite		$	5,871		$	5,871
Customer relationships		11		10,644			9,849
Non-compete agreements		5		157			—
				16,672			15,720
Less accumulated amortization				(9,338	)		(8,466	)
			$	7,334		$	7,254

Segment Reporting (Tables)

12 Months Ended

Dec. 31, 2019

Segment Reporting [Abstract]

Summarized Financial Information for Company's Reportable Segments

Summarized financial information for the years ended December 31, 2019, 2018 and 2017, for the Company’s reportable segments is shown in the following tables:

(dollar amounts in thousands)	Mobile Modular			TRS- RenTelco			Adler Tanks			Enviroplex ¹			Consolidated
Year Ended December 31,
2019
Rental revenues	$	182,316		$	103,704		$	67,869		$	—		$	353,889
Rental related services revenues		69,395			3,260			28,383		—				101,038
Sales and other revenues		49,299			24,519			1,671			39,814			115,303
Total revenues		301,010			131,483			97,923			39,814			570,230
Depreciation of rental equipment		22,071			41,948			16,372		—				80,391
Gross profit		143,618			60,748			47,014			14,785			266,165
Selling and administrative expenses		65,699			24,645			29,321			5,128			124,793
Income from operations		77,919			36,103			17,693			9,657			141,372
Interest expense (income) allocation		7,946			1,970			3,436			(1,021	)		12,331
Income before provision for income taxes		69,973			34,217			14,257			10,678			129,125
Rental equipment acquisitions		75,433			89,759			4,826		—				170,018
Accounts receivable, net (period end)		83,182			23,788			17,281			3,848			128,099
Rental equipment, at cost (period end)		868,807			335,343			316,261		—				1,520,411
Rental equipment, net book value (period end)		610,048			172,413			185,039		—				967,500
Utilization (period end) ²		79.1	%		64.5	%		48.4	%
Average utilization ²		79.2	%		66.2	%		54.7	%

Segment Data (Continued) (dollar amounts in thousands)	Mobile Modular			TRS- RenTelco			Adler Tanks			Enviroplex 1		Consolidated
Year Ended December 31,
2018
Rental revenues	$	159,136		$	89,937		$	69,701		$	—	$	318,774
Rental related services revenues		54,696			3,300			24,911		—			82,907
Sales and other revenues		40,742			25,420			1,441			29,046		96,649
Total revenues		254,574			118,657			96,053			29,046		498,330
Depreciation of rental equipment		21,200			36,011			15,928		—			73,139
Gross profit		120,750			54,773			48,055			9,673		233,251
Selling and administrative expenses		58,017			22,823			30,026			4,904		115,770
Income from operations		62,733			31,950			18,029			4,769		117,481
Interest expense (income) allocation		(7,132	)		(2,696	)		(3,252	)		783		(12,297	)
Income before benefit for income taxes		55,601			28,765			14,777			5,552		104,695
Rental equipment acquisitions		63,374			65,467			5,257		—			134,098
Accounts receivable, net (period end)		72,295			20,732			19,992			7,997		121,016
Rental equipment, at cost (period end)		817,375			285,052			313,573		—			1,416,000
Rental equipment, net book value (period end)		572,032			131,450			197,533		—			901,015
Utilization (period end) 2		79.3	%		62.1	%		56.4	%
Average utilization 2		78.2	%		62.7	%		59.9	%

2017
Rental revenues	$	142,584		$	82,812		$	64,021		$	—	$	289,417
Rental related services revenues		50,448			2,858			24,762		—			78,068
Sales and other revenues		38,234			22,374			2,572			31,369		94,549
Total revenues		231,266			108,044			91,355			31,369		462,034
Depreciation of rental equipment		21,247			32,891			15,770		—			69,908
Gross profit		103,935			50,289			43,218			8,903		206,345
Selling and administrative expenses		55,583			22,171			29,542			4,309		111,605
Income from operations		48,352			28,118			13,676			4,594		94,740
Interest expense (income) allocation		(6,671	)		(2,320	)		(3,071	)		440		(11,622	)
Income before provision for income taxes		41,681			26,132			10,605			5,034		83,452
Rental equipment acquisitions		34,526			58,781			4,800		—			98,107
Accounts receivable, net (period end)		59,274			19,581			18,663			8,354		105,872
Rental equipment, at cost (period end)		775,400			262,325			309,808		—			1,347,533
Rental equipment, net book value (period end)		543,857			109,482			208,981		—			862,320
Utilization (period end) 2		77.8	%		61.7	%		57.5	%
Average utilization 2		76.8	%		62.9	%		56.0	%

1	Gross Enviroplex sales revenues were $39,814, $30,407 and $31,369 in 2019, 2018 and 2017, respectively. There were $1,361 inter-segment sales to Mobile Modular in 2018, which have been eliminated in consolidation. There were no inter-segment sales in 2019 and 2017.

2	Utilization is calculated each month by dividing the cost of rental equipment on rent by the total cost of rental equipment excluding new equipment inventory and accessory equipment. The average utilization for the period is calculated using the average costs of rental equipment.

Quarterly Financial Information (Tables)

12 Months Ended

Dec. 31, 2019

Quarterly Financial Information Disclosure [Abstract]

Quarterly Financial Information

Quarterly financial information for each of the two years ended December 31, 2019 is summarized below:

(in thousands, except per share amounts)	2019
	First		Second		Third		Fourth		Year
Operations Data
Rental revenues	$	82,696	$	88,105	$	90,857	$	92,231	$	353,889
Total revenues		122,008		127,439		173,562		147,221		570,230
Gross profit		57,005		59,881		78,282		70,997		266,165
Income from operations		27,310		29,066		46,748		38,248		141,372
Income before provision for income taxes		24,251		25,965		43,455		35,454		129,125
Net income		18,449		19,488		32,468		26,401		96,806
Earnings per share:
Basic	$	0.76	$	0.80	$	1.34	$	1.09	$	3.99
Diluted	$	0.75	$	0.79	$	1.32	$	1.07	$	3.93
Dividends declared per share	$	0.375	$	0.375	$	0.375	$	0.375	$	1.50
Shares used in per share calculations:
Basic		24,195		24,246		24,268		24,290		24,250
Diluted		24,540		24,579		24,632		24,697		24,623
Balance Sheet Data
Rental equipment, net	$	912,878	$	943,152	$	958,610	$	967,500	$	967,500
Total assets		1,239,633		1,280,249		1,306,223		1,309,875		1,309,875
Notes payable		289,464		301,878		301,469		293,431		293,431
Shareholders’ equity		580,643		592,309		616,715		634,036		634,036

	2018
	First		Second		Third		Fourth		Year
Operations Data
Rental revenues	$	74,261	$	77,267	$	82,155	$	85,091	$	318,774
Total revenues		105,085		116,983		143,147		133,115		498,330
Gross profit		50,170		53,928		64,050		65,103		233,251
Income from operations		22,042		24,449		35,824		35,166		117,481
Income before provision for income taxes		19,018		21,106		32,553		32,018		104,695
Net income		14,466		15,912		24,779		24,249		79,406
Earnings per share:
Basic	$	0.60	$	0.66	$	1.03	$	1.00	$	3.29
Diluted	$	0.59	$	0.65	$	1.01	$	0.99	$	3.24
Dividends declared per share	$	0.34	$	0.34	$	0.34	$	0.34	$	1.36
Shares used in per share calculations:
Basic		24,067		24,145		24,172		24,179		24,141
Diluted		24,478		24,584		24,563		24,514		24,540
Balance Sheet Data
Rental equipment, net	$	865,338	$	876,522	$	888,607	$	901,015	$	901,015
Total assets		1,148,858		1,180,209		1,201,799		1,217,316		1,217,316
Notes payable		300,595		314,860		309,006		298,564		298,564
Shareholders’ equity		530,284		537,195		554,547		571,535		571,535

Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019 USD ($) Division Segment shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 USD ($) shares	Aug. 31, 2015 shares
Summary Of Significant Accounting Policies [Line Items]
Number of divisions \| Division	4
Number of reportable segments \| Segment	4
Impairments of long-lived assets	$ 0	$ 39,000	$ 1,639,000
Period for warranties for rental equipment	90 days
Period for warranties for equipment manufactured	1 year
Property, plant and equipment depreciation expenses	$ 8,200,000	8,000,000.0	7,600,000
Capitalized in internal use of software	3,000,000.0	100,000
Total advertising expenses	$ 3,600,000	3,200,000	2,900,000
Estimated useful life in years, Customer relationships	11 years
Goodwill and trade name intangible assets	$ 34,100,000	33,700,000
Goodwill and intangible assets impairment charge	$ 0	$ 0	$ 0
Options to purchase common stock \| shares	0	0	7,000
Common stock shares authorized for repurchase \| shares				2,000,000
Common stock repurchased \| shares	0	0	0
Shares remain authorized for repurchase \| shares	1,592,026
Unbilled receivables related to end-of-lease services	$ 37,200,000	$ 32,300,000
Period for credit risk identified	30 days
Estimated fair value notes payable	$ 101,400,000	99,000,000.0
Recorded fair value of notes payable	$ 100,000,000.0	100,000,000.0
Modular Rental Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Impairments of long-lived assets		$ 100,000	$ 1,600,000

Summary of Significant Accounting Policies - Estimated Useful Lives and Residual Values of Company's Rental Equipment (Detail)	12 Months Ended
	Dec. 31, 2019
Relocatable modular buildings [Member]
Property, Plant and Equipment [Line Items]
Property subject to or available for operating lease useful life	18 years
Percentage residual value property subject to or available for operating lease	50.00%
Relocatable modular accessories [Member]
Property, Plant and Equipment [Line Items]
Percentage residual value property subject to or available for operating lease	0.00%
Blast resistant modules [Member]
Property, Plant and Equipment [Line Items]
Property subject to or available for operating lease useful life	20 years
Percentage residual value property subject to or available for operating lease	0.00%
Portable storage containers [Member]
Property, Plant and Equipment [Line Items]
Property subject to or available for operating lease useful life	25 years
Percentage residual value property subject to or available for operating lease	62.50%
Electronic test equipment and accessories [Member]
Property, Plant and Equipment [Line Items]
Percentage residual value property subject to or available for operating lease	0.00%
Liquid and solid containment tanks and boxes and accessories [Member]
Property, Plant and Equipment [Line Items]
Percentage residual value property subject to or available for operating lease	0.00%
Minimum [Member] \| Relocatable modular accessories [Member]
Property, Plant and Equipment [Line Items]
Property subject to or available for operating lease useful life	3 years
Minimum [Member] \| Electronic test equipment and accessories [Member]
Property, Plant and Equipment [Line Items]
Property subject to or available for operating lease useful life	1 year
Minimum [Member] \| Liquid and solid containment tanks and boxes and accessories [Member]
Property, Plant and Equipment [Line Items]
Property subject to or available for operating lease useful life	3 years
Maximum [Member] \| Relocatable modular accessories [Member]
Property, Plant and Equipment [Line Items]
Property subject to or available for operating lease useful life	18 years
Maximum [Member] \| Electronic test equipment and accessories [Member]
Property, Plant and Equipment [Line Items]
Property subject to or available for operating lease useful life	8 years
Maximum [Member] \| Liquid and solid containment tanks and boxes and accessories [Member]
Property, Plant and Equipment [Line Items]
Property subject to or available for operating lease useful life	20 years

Summary of Significant Accounting Policies - Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 215,083	$ 201,392
Less accumulated depreciation	(84,308)	(77,118)
Property plant and equipment net excluding capitalized cost	130,775	124,274
Construction in progress	272	2,625
Property, Plant and Equipment, net	131,047	126,899
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 54,423	50,689
Estimated useful life	Indefinite
Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 52,325	50,064
Land Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	20 years
Land Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	50 years
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 29,848	29,359
Estimated useful life	30 years
Furniture, Office and Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 36,610	33,081
Furniture, Office and Computer Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Furniture, Office and Computer Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	10 years
Vehicles and Machinery [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 41,877	$ 38,199
Vehicles and Machinery [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	5 years
Vehicles and Machinery [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	25 years

Summary of Significant Accounting Policies - Weighted-Average Common Stock Used to Calculate Basic and Diluted Earnings Per Share (Detail) - shares shares in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Weighted-average common stock for calculating basic earnings per share	24,290	24,268	24,246	24,195	24,179	24,172	24,145	24,067	24,250	24,141	23,999
Effect of potentially dilutive securities from equity-based compensation									373	399	270
Weighted-average common stock for calculating diluted earnings per share	24,697	24,632	24,579	24,540	24,514	24,563	24,584	24,478	24,623	24,540	24,269

Summary of Significant Accounting Policies - Summary of Allowance for Doubtful Accounts Activity (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Allowance for doubtful accounts, Beginning Balance	$ 1,883	$ 1,920
Provision for doubtful accounts	1,013	581	$ 1,480
Write-offs, net of recoveries	(1,013)	(618)
Allowance for doubtful accounts, Ending Balance	$ 1,883	$ 1,883	$ 1,920

Implemented Accounting Pronouncements - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Jan. 01, 2019
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Lessee, operating lease, description	The Company leases real estate for certain of its branch offices and rental equipment storage yards, vehicles and equipment used in its rental operations. The Company determines if an arrangement is a lease at inception. The Company has leases with lease and non-lease components, which are accounted for separately.
Lessee, operating lease, option to extend	true
Lessee, operating lease, option to extend, description	These leases include one or more options to renew, with renewal terms that may extend the lease term from one to three years.
Operating lease, right of use assets	$ 10,000,000.0
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PrepaidExpenseAndOtherAssets
Operating lease liabilities	$ 9,945,000	$ 10,000,000.0
Operating Lease, Liability, Statement of Financial Position [Extensible List]	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent
Operating lease expense	$ 3,800,000
Short term lease expense	$ 200,000
Weighted-average remaining lease term for operating leases	3 years 9 months 18 days
Weighted-average discount rate for operating leases	4.38%
Sub-lease income	$ 0
Finance lease liability	$ 0
Lessor, operating lease, description	The Company’s equipment rentals for each of its operating segments are governed by agreements that detail the lease terms and conditions. The determination of whether these contracts with customers contain a lease generally does not require significant judgement. The Company accounts for these rentals as operating leases.
Lessor, operating lease, option to extend	true
Lessor, operating lease, option to extend description	Initial lease terms vary in length based upon customer needs and generally range from one to sixty months.
Lease revenue	$ 411,000,000.0
Operating lease revenue	407,600,000
Finance lease revenue	3,400,000
Finance lease revenue, sales revenue	3,100,000
Finance lease revenue, interest income	$ 300,000
Minimum [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Lessee, operating lease, renewal term	1 year
Lessor, operating lease, renewal term	1 month
Lessor, operating lease, rental products, useful lives	3 years
Maximum [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Lessee, operating lease, renewal term	3 years
Lessor, operating lease, renewal term	60 months
Lessor, operating lease, rental products, useful lives	5 years

Implemented Accounting Pronouncements - Summary of Supplemental Cash flow Information Related to Leases (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 3,568
Right of use assets obtained in exchange for lease obligations:
Operating leases	$ 2,728

Implemented Accounting Pronouncements - Summary of Maturities of Operating Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019
Operating Lease Liabilities Payments Due [Abstract]
2020	$ 3,350
2021	2,794
2022	1,958
2023	1,458
2024	915
Thereafter	293
Total lease payments	10,768
Less imputed interest	(823)
Operating lease liabilities	$ 9,945	$ 10,000

Implemented Accounting Pronouncements - Summary of Maturities of Operating Lease Payments (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Lessor Operating Lease Payments Fiscal Year Maturity [Abstract]
2020	$ 92,821
2021	30,926
2022	8,922
2023	2,145
2024	877
Thereafter	37
Operating lease, payments to be received	$ 135,728

Implemented Accounting Pronouncements - Minimum Lease Payments Receivable and Net Investment Included in Accounts Receivable for Leases (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Minimum lease payments receivable and net investment included in accounts receivable for leases
Gross minimum lease payments receivable	$ 3,218
Less – unearned interest	(289)
Net investment in finance lease receivables	$ 2,929

Implemented Accounting Pronouncements - Future Minimum Lease Payments under Non-Cancelable Finance Leases (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Future minimum lease payments under non-cancelable finance leases
2020	$ 2,345
2021	629
2022	184
2023	50
2024	10
Total minimum future lease payments	$ 3,218

Revenue Recognition - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disaggregation Of Revenue [Line Items]
Period for credit risk identified	30 days
Sales revenues totaling	$ 10.2
Unbilled contract assets	$ 37.2	$ 32.3
Period for warranties for rental equipment	90 days
Period for warranties for equipment manufactured	1 year
Deferred Income [Member]
Disaggregation Of Revenue [Line Items]
Customer contract liability	$ 17.5	15.7
Accounts Receivable [Member]
Disaggregation Of Revenue [Line Items]
Unbilled contract assets	$ 1.0	$ 1.4

Revenue Recognition - Summary of Disaggregates the Company's Revenue by Lease and Non Lease (Detail) - USD ($)
$ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2019

Sep. 30, 2019

Jun. 30, 2019

Mar. 31, 2019

Dec. 31, 2018

Sep. 30, 2018

Jun. 30, 2018

Mar. 31, 2018

Dec. 31, 2019

Dec. 31, 2018

Dec. 31, 2017

$ 411,000

115,303

$ 96,649

$ 94,549

$ 147,221

$ 173,562

$ 127,439

$ 122,008

$ 133,115

$ 143,147

$ 116,983

$ 105,085

570,230

498,330

462,034

Leasing [Member]

Non-lease Rental Related Services [Member]

410,993

365,212

331,218

49,197

41,753

40,011

Non-lease Sales [Member]

107,120

89,452

89,302

Non-lease Other [Member]

Non-lease Revenues [Member]

2,920

1,913

1,503

159,237

133,118

130,816

Mobile Modular [Member]

49,299

40,742

38,234

Mobile Modular [Member] | Leasing [Member]

301,010

254,574

231,266

Mobile Modular [Member] | Non-lease Rental Related Services [Member]

234,032

200,214

180,612

Mobile Modular [Member] | Non-lease Sales [Member]

18,964

14,870

13,331

Mobile Modular [Member] | Non-lease Other [Member]

47,045

39,467

37,434

Mobile Modular [Member] | Non-lease Revenues [Member]

969

(111)

66,978

54,360

50,654

TRS-RenTelco [Member]

24,519

25,420

22,374

TRS-RenTelco [Member] | Leasing [Member]

131,483

118,657

108,044

TRS-RenTelco [Member] | Non-lease Rental Related Services [Member]

108,044

94,345

85,930

TRS-RenTelco [Member] | Non-lease Sales [Member]

2,599

2,607

2,358

TRS-RenTelco [Member] | Non-lease Other [Member]

18,995

19,895

18,137

TRS-RenTelco [Member] | Non-lease Revenues [Member]

1,845

1,810

1,619

23,439

24,312

22,114

Adler Tanks [Member]

1,671

1,441

2,572

Adler Tanks [Member] | Leasing [Member]

97,923

96,053

91,355

Adler Tanks [Member] | Non-lease Rental Related Services [Member]

68,917

70,653

64,676

Adler Tanks [Member] | Non-lease Sales [Member]

27,634

24,276

24,322

Adler Tanks [Member] | Non-lease Other [Member]

1,266

1,044

2,362

Adler Tanks [Member] | Non-lease Revenues [Member]

106

(5)

29,006

25,400

26,679

Enviroplex [Member]

^[1]

39,814

29,046

31,369

Enviroplex [Member] | Non-lease Sales [Member]

^[1]

39,814

29,046

31,369

Enviroplex [Member] | Non-lease Revenues [Member]

39,814

29,046

31,369

$ 39,814

$ 29,046

$ 31,369

[1]	Gross Enviroplex sales revenues were $39,814, $30,407 and $31,369 in 2019, 2018 and 2017, respectively. There were $1,361 inter-segment sales to Mobile Modular in 2018, which have been eliminated in consolidation. There were no inter-segment sales in 2019 and 2017.

Notes Payable - Components of Notes Payable (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018
Debt Instrument [Line Items]
Notes payable	$ 293,459				$ 298,603
Unamortized debt issuance cost	(28)				(39)
Notes payable, net	293,431	$ 301,469	$ 301,878	$ 289,464	298,564	$ 309,006	$ 314,860	$ 300,595
Unsecured Revolving Lines of Credit [Member]
Debt Instrument [Line Items]
Notes payable	193,459				198,603
Series B senior notes [Member] \| 3.68% Series B senior notes due in 2021 [Member]
Debt Instrument [Line Items]
Notes payable	40,000				40,000
Series C senior notes [Member] \| 3.84% Series C senior notes due in 2022 [Member]
Debt Instrument [Line Items]
Notes payable	$ 60,000				$ 60,000

Notes Payable - Components of Notes Payable (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2019	Nov. 05, 2015	Mar. 17, 2014
Series B senior notes [Member] \| 3.68% Series B senior notes due in 2021 [Member]
Debt Instrument [Line Items]
Senior Notes, interest rate	3.68%		3.68%
Senior Notes, year of maturity	2021
Series C senior notes [Member] \| 3.84% Series C senior notes due in 2022 [Member]
Debt Instrument [Line Items]
Senior Notes, interest rate	3.84%	3.84%
Senior Notes, year of maturity	2022

Notes Payable - Schedule of Future Minimum Payments under Unsecured Revolving Lines of Credit and 3.68% Senior Notes and 3.84% Senior Notes (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Notes payable	$ 293,459	$ 298,603
Notes Payable to Banks and Others [Member]
Debt Instrument [Line Items]
2021	233,459
2022	60,000
Notes payable	$ 293,459

Notes Payable - Additional Information (Detail) - USD ($)			12 Months Ended
	Nov. 05, 2015	Mar. 17, 2014	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2016
Debt Instrument [Line Items]
Consolidated Fixed Charge Coverage Ratio			2.50%
Consolidated Fixed Charge Coverage Ratio, actual			4.27%
Consolidated Leverage Ratio			275.00%
Consolidated Leverage Ratio, actual			124.00%
Line of credit facility covenants tangible net worth description			Permit Tangible Net Worth, calculated as of the last day of each fiscal quarter, to be less than the sum of (i) $229.0 million, plus (ii) 25% of net income for such fiscal quarter subsequent to December 31, 2010, plus (iii) 90% of the net cash proceeds from the issuance of the Company’s capital stock after December 31, 2010.
Tangible Net Worth sum			$ 388,100,000
Consolidated Net Income			25.00%
Percentage of net cash proceeds from issuance of capital stock			90.00%
Actual tangible net worth			$ 598,500,000
Senior notes principal balance outstanding			$ 293,459,000	$ 298,603,000
Series B Senior Notes [Member] \| 3.68% Series B senior notes due in 2021 [Member]
Debt Instrument [Line Items]
Proceeds from issuance of senior notes		$ 40,000,000.0
Senior notes interest rate		3.68%	3.68%
Debt instrument, maturity date			Mar. 17, 2021
Senior notes description			The Series B Senior Notes are an unsecured obligation of the Company, bear interest at a rate of 3.68% per annum and mature on March 17, 2021. Interest on the Series B Senior Notes is payable semi-annually beginning on September 17, 2014 and continuing thereafter on March 17 and September 17 of each year until maturity.
Senior notes interest payment			Semi-annually
Senior notes principal balance outstanding			$ 40,000,000	40,000,000
Series C Senior Notes [Member] \| 3.84% Series C senior notes due in 2022 [Member]
Debt Instrument [Line Items]
Proceeds from issuance of senior notes	$ 60,000,000.0
Senior notes interest rate	3.84%		3.84%
Debt instrument, maturity date			Nov. 05, 2022
Senior notes description			November 5, 2022. Interest on the Series C Senior Notes is payable semi-annually beginning on May 5, 2016 and continuing thereafter on November 5 and May 5 of each year until maturity.
Senior notes interest payment			semi-annually
Senior notes principal balance outstanding			$ 60,000,000	$ 60,000,000
Debt instrument, date of first required payment			May 05, 2016
Minimum [Member]
Debt Instrument [Line Items]
Credit facility, maximum					$ 10,000,000.0
Tangible Net Worth sum			$ 229,000,000.0
Maximum [Member]
Debt Instrument [Line Items]
Credit facility, maximum					$ 12,000,000.0
Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility, maturity period			5 years
Revolving credit facility, maturity date			Mar. 31, 2021
Credit facility, maximum			$ 420,000,000.0
Revolving credit facility, available maximum borrowing capacity			620,000,000.0
Additional commitments			$ 200,000,000.0
Consolidated Fixed Charge Coverage Ratio			2.50%
Consolidated Fixed Charge Coverage Ratio, actual			4.27%
Consolidated Leverage Ratio			275.00%
Consolidated Leverage Ratio, actual			124.00%
Line of credit facility covenants tangible net worth description			Permit Tangible Net Worth as of the end of any fiscal quarter of the Company to be less than the sum of (i) $246.1 million plus (ii) 25% of the Company’s Consolidated Net Income (as defined in the Amended Credit Facility) (but only if a positive number) for each fiscal quarter ended subsequent to December 31, 2011
Tangible Net Worth sum			$ 388,100,000
Consolidated Net Income			25.00%
Percentage of net cash proceeds from issuance of capital stock			90.00%
Actual tangible net worth			$ 598,500,000
Debt instrument description of variable rate basis			(i) LIBOR plus a defined margin, or (ii) the Agent bank’s prime rate (“base rate”) plus a margin. The applicable margin for each type of loan is measured based upon the Consolidated Leverage Ratio at the end of the prior fiscal quarter and ranges from 1.00% to 1.75% for LIBOR loans and 0% to 0.75% for base rate loans. In addition, the Company pays an unused commitment fee for the portion of the $420.0 million credit facility that is not used. These fees are based upon the Consolidated Leverage Ratio and range from 0.15% to 0.30%. As of December 31, 2019 and 2018, the applicable margins were 1.25% for LIBOR based loans, 0.25% for base rate loans and 0.20% for unused fees. Amounts borrowed under the Sweep Service Facility are based upon the MUFG Union Bank, N.A. base rate plus an applicable margin and an unused commitment fee for the portion of the $12.0 million facility not used.
Unused commitment fees			$ 420,000,000.0
Credit Facility [Member] \| Unused Fees [Member]
Debt Instrument [Line Items]
Debt instrument interest rate at period end			0.20%	0.20%
Credit Facility [Member] \| LIBOR Loans [Member]
Debt Instrument [Line Items]
Debt instrument interest rate at period end			1.25%	1.25%
Credit Facility [Member] \| Base Rate Loans [Member]
Debt Instrument [Line Items]
Debt instrument interest rate at period end			0.25%	0.25%
Credit Facility [Member] \| Sweep Service Facility [Member]
Debt Instrument [Line Items]
Credit facility, maximum			$ 432,000,000.0
Revolving credit facility, available maximum borrowing capacity			238,500,000
Amount outstanding			193,500,000
Unused commitment fees			12,000,000.0
Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Tangible Net Worth sum			$ 246,100
Leverage ratio			0.15%
Credit Facility [Member] \| Minimum [Member] \| LIBOR Loans [Member]
Debt Instrument [Line Items]
Leverage ratio			1.00%
Credit Facility [Member] \| Minimum [Member] \| Base Rate Loans [Member]
Debt Instrument [Line Items]
Leverage ratio			0.00%
Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Leverage ratio			0.30%
Credit Facility [Member] \| Maximum [Member] \| LIBOR Loans [Member]
Debt Instrument [Line Items]
Leverage ratio			1.75%
Credit Facility [Member] \| Maximum [Member] \| Base Rate Loans [Member]
Debt Instrument [Line Items]
Leverage ratio			0.75%
Unsecured revolving credit facility before Renewal [Member]
Debt Instrument [Line Items]
Credit facility, maximum			$ 420,000,000.0
Letters of Credit [Member]
Debt Instrument [Line Items]
Credit facility, maximum			25,000,000.0
Swingline Loans [Member]
Debt Instrument [Line Items]
Credit facility, maximum			$ 10,000,000.0

Income Taxes - Schedule of Income Before Provision (Benefit) for Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest [Abstract]
U.S.									$ 129,045	$ 104,881	$ 83,525
Foreign									80	(186)	(73)
Income before provision for income taxes	$ 35,454	$ 43,455	$ 25,965	$ 24,251	$ 32,018	$ 32,553	$ 21,106	$ 19,018	$ 129,125	$ 104,695	$ 83,452

Income Taxes - Provision (Benefit) for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
U.S. Federal	$ 11,744	$ 7,270	$ 21,171
State	7,353	4,253	2,976
Foreign	1,616	1,731	2,016
Current income tax expense (benefit)	20,713	13,254	26,163
Deferred:
U.S. Federal	10,719	10,355	(103,518)
State	895	1,637	6,948
Foreign	(8)	43	(61)
Deferred income tax expense (benefit)	11,606	12,035	(96,631)
Total	$ 32,319	$ 25,289	$ (70,468)

Income Taxes - Reconciliation of U.S. Federal Statutory Tax Rate to Company's Effective Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
U.S. federal statutory rate	21.00%	21.00%	35.00%
State taxes, net of federal benefit	5.00%	5.00%	4.10%
State deferred tax rate change, net of federal benefit	0.10%	0.70%	0.50%
Valuation allowance	0.00%	(0.50%)	0.10%
Share-based compensation	(1.60%)	(1.90%)	(1.00%)
Enactment of the Tax Cuts and Jobs Act	(0.10%)	(0.10%)	(123.00%)
Other	0.60%	0.00%	(0.20%)
Effective Income Tax Rate	25.00%	24.20%	(84.40%)

Income Taxes - Deferred Income Taxes Related to Temporary Differences between Tax Bases of Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax liabilities:
Accelerated depreciation	$ 221,627	$ 208,539
Prepaid costs currently deductible	5,668	4,845
Other	5,011	4,703
Total deferred tax liabilities	232,306	218,087
Deferred tax assets:
Accrued costs not yet deductible	8,860	7,796
Allowance for doubtful accounts	486	486
Deferred revenues	2,512	1,774
Share-based compensation	2,178	1,367
Total deferred tax assets, net of valuation allowance of $0.2 million in 2019 and 2018	14,036	11,423
Deferred income taxes, net	$ 218,270	$ 206,664

Income Taxes - Deferred Income Taxes Related to Temporary Differences between Tax Bases of Assets and Liabilities (Parenthetical) (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Deferred tax assets, valuation allowance	$ 0.2	$ 0.2

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Federal corporate tax rate	21.00%	21.00%	35.00%
Deferred tax liability related to foreign earnings	$ 0
Excess tax shortfall (benefit) from exercise of share-based awards	$ (2,100,000)	$ (2,000,000.0)	$ (900,000)
Likelihood percentage of being realized upon ultimate settlement with the relevant tax authority	50.00%
Unrecognized tax benefits	$ 0	0
Changes in unrecognized benefits	0	$ 0	$ 0
Foreign [Member]
Operating Loss Carryforwards [Line Items]
Net operating losses carryforwards	$ 600,000
Net operating losses carryforwards, expiration year	2023

Benefit Plans - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 08, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 5,892,000	$ 4,111,000	$ 3,198,000
Tax benefit related to share-based compensation expense	1,600,000	1,100,000	1,300,000
Capitalized share-based compensation expense	$ 0	$ 0	$ 0
Stock option plans remain outstanding	580,140	845,600	1,208,860	1,584,435
Weighted average grant date fair value			$ 6.28
Number of options, granted	0	0	299,600
Eligible period of service for participation in plan	3 months
Minimum age for employees to participate in KSOP	21 years
Dividends deducted	$ 400,000
Tax benefit from dividends	$ 100,000
Shares outstanding, employee stock ownership plan	241,956
Percentage of total common shares outstanding	1.00%
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized	1,708,914
Stock options granted	8,458,600
Stock options, exercise prices lower	$ 3.47
Stock options, exercise prices upper	$ 40.37
Purchase of shares	6,214,548
Stock option shares terminated	1,663,912
Stock option plans remain outstanding	580,140
Stock options outstanding, exercise prices lower	$ 24.60
Stock options outstanding, exercise prices upper	$ 40.37
Stock options vesting period	5 years
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	7 years
Options issued to non-employee advisors	0
Aggregate intrinsic value of options exercised and sold	$ 9,100,000	$ 9,000,000.0	$ 5,000,000.0
Total unrecognized compensation cost	$ 1,400,000
Expected recognition period of unrecognized compensation expense	1 year 1 month 6 days
Performance-based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period	3 years	5 years	5 years
Percentage of vesting annually at anniversary			20.00%
Number of RSU's expected to vest	200,839
Performance-based RSUs [Member] \| Vesting after three years [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vesting RSUs	100.00%	100.00%	60.00%
Service-based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSU's expected to vest	81,984
Number of forfeitures expected	0
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected recognition period of unrecognized compensation expense	2 years 1 month 6 days
Number of forfeitures expected	840	21,200	66,200
Total fair value of RSU's vested based on weighted average grant date values	$ 1,200,000	$ 1,000,000.0	$ 1,000,000.0
Stock-based compensation expense for restricted stock	4,700,000	$ 2,600,000	$ 1,400,000
Total unrecognized compensation expense net of forfeitures	$ 6,900,000
Maximum [Member] \| Service-based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period	14 months
Minimum [Member] \| Service-based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period	12 months
2016 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in common stock available for grant	2
Common Stock [Member] \| 2016 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock remained available for grants of awards					2,000,000
Common Stock [Member] \| 2016 Stock Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of award (in years)	7 years
Common Stock [Member] \| 2016 Stock Incentive Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Rate of exercise price for equity award granted	100.00%

Benefit Plans - Summary of Company's Option Activity (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Options, Beginning Balance	845,600	1,208,860	1,584,435
Number of Options, granted	0	0	299,600
Number of Options, exercised	(260,860)	(332,810)	(398,275)
Number of Options, cancelled/forfeited/expired	(4,600)	(30,450)	(276,900)
Number of Options, Ending Balance	580,140	845,600	1,208,860
Number of Options, Exercisable at December 31, 2019	289,350
Number of Options, Expected to Vest after December 31, 2019	289,003
Weighted-Average Price, Beginning Balance	$ 28.14	$ 28.14	$ 28.14
Weighted-Average Price, Options granted			34.66
Weighted-Average Price, Options exercised	29.55	29.49	28.94
Weighted-Average Price, Options cancelled/forfeited/expired	30.59	28.27	28.04
Weighted-Average Price, Ending Balance	29.57	$ 28.14	$ 28.14
Weighted-Average Price, Exercisable at December 31, 2019	29.35
Weighted-Average Price, Expected to Vest after December 31, 2019	$ 29.80
Weighted-Average Remaining Contractual Term, Balance At December 31, 2019	3 years 3 months 21 days
Weighted-Average Remaining Contractual Term, Exercisable at December 31, 2019	3 years
Weighted-Average Remaining Contractual Term, Expected to Vest after December 31, 2019	3 years 7 months 9 days
Aggregate Intrinsic Value, Balance At December 31, 2019	$ 27.2
Aggregate Intrinsic Value, Exercisable at December 31, 2019	13.6
Aggregate Intrinsic Value, Expected to Vest after December 31, 2019	$ 13.5

Benefit Plans - Options Outstanding and Options Exercisable by Exercise Price with Weighted-Average Remaining Contractual Life for Options Outstanding and Weighted-Average Exercise Price (Detail)	12 Months Ended
	Dec. 31, 2019 $ / shares shares
Exercise Price 20-25 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	$ 20
Exercise Price Upper Range Limit	$ 25
Options Outstanding, Number \| shares	256,640
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	3 years 2 months 1 day
Options Outstanding, Weighted-Average Grant Date Value	$ 24.60
Options Exercisable, Number \| shares	128,440
Options Exercisable, Weighted-Average Grant Date Value	$ 24.60
Exercise Price 25-30 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	25
Exercise Price Upper Range Limit	$ 30
Options Outstanding, Number \| shares	6,150
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	3 years 1 month 17 days
Options Outstanding, Weighted-Average Grant Date Value	$ 25.13
Options Exercisable, Number \| shares	1,120
Options Exercisable, Weighted-Average Grant Date Value	$ 25.14
Exercise Price 30-35 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	30
Exercise Price Upper Range Limit	$ 35
Options Outstanding, Number \| shares	306,810
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	3 years 4 months 24 days
Options Outstanding, Weighted-Average Grant Date Value	$ 33.48
Options Exercisable, Number \| shares	155,710
Options Exercisable, Weighted-Average Grant Date Value	$ 33.04
Exercise Price 35-40 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	35
Exercise Price Upper Range Limit	$ 40
Options Outstanding, Number \| shares	6,800
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	4 years
Options Outstanding, Weighted-Average Grant Date Value	$ 39.19
Options Exercisable, Number \| shares	4,080
Options Exercisable, Weighted-Average Grant Date Value	$ 39.19
Exercise Price 40-45 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	40
Exercise Price Upper Range Limit	$ 45
Options Outstanding, Number \| shares	3,740
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	4 years 8 months 1 day
Options Outstanding, Weighted-Average Grant Date Value	$ 40.37
Exercise Price 20-45 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	20
Exercise Price Upper Range Limit	$ 45
Options Outstanding, Number \| shares	580,140
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	3 years 3 months 21 days
Options Outstanding, Weighted-Average Grant Date Value	$ 29.57
Options Exercisable, Number \| shares	289,350
Options Exercisable, Weighted-Average Grant Date Value	$ 29.35

Benefit Plans - Schedule of Weighted-Average Assumptions Used to Determine Fair Value of Option Granted (Detail)	12 Months Ended
	Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Expected term (in years)	5 years
Expected volatility	26.10%
Expected dividend yields	3.00%
Risk-free interest rates	2.00%

Benefit Plans - Summary of Company's Restricted Stock Units Activity (Detail) - Restricted Stock Units [Member] - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Beginning Balance	139,510	93,664	125,240
Number of Shares, granted	83,440	97,260	70,960
Number of Shares, vested	(25,862)	(30,214)	(36,336)
Number of Shares, cancelled/forfeited/expired	(840)	(21,200)	(66,200)
Number of Shares, Ending Balance	196,248	139,510	93,664
Weighted-Average Grant Date Fair Value, Beginning Balance	$ 44.73	$ 33.62	$ 30.66
Weighted-Average Grant Date Fair Value, granted	59.98	49.47	34.53
Weighted-Average Grant Date Fair Value, vested	48.31	33.16	26.99
Weighted-Average Grant Date Fair Value, cancelled/forfeited/expired	59.84	33.88	32.63
Weighted-Average Grant Date Fair Value, Ending Balance	$ 50.68	$ 44.73	$ 33.62
Aggregate Intrinsic Value	$ 15.0

Shareholders' Equity - Additional Information (Detail) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Aug. 31, 2015
Stockholders Equity Note [Abstract]
Common stock shares authorized for repurchase				2,000,000
Shares remain authorized for repurchase	1,592,026
Common stock repurchased, Shares	0	0	0

Commitments and Contingencies - Minimum Payments under Leases, Exclusive of Property Taxes and Insurance (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Operating Leases Future Minimum Payments Due [Abstract]
2020	$ 2,732
2021	2,370
2022	1,805
2023	1,290
2024	1,005
Thereafter	293
Total minimum future lease payments	$ 9,495

Commitments and Contingencies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Commitments And Contingencies Disclosure [Abstract]
Facility rent expense	$ 3,900,000	$ 3,500,000	$ 3,500,000
Health plan annual stop-loss insurance per claim	200,000
Workers compensation insurance with no stop-loss for prior claim years	350,000
Accruals for health and workers' compensation plans	$ 2,800,000	$ 3,000,000.0

Intangible Assets - Summary of Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Finite Lived Intangible Assets [Line Items]
Trade name	$ 5,871	$ 5,871
Customer relationships	10,644	9,849
Non-compete agreements	157
Intangible Assets, gross	16,672	15,720
Less accumulated amortization	(9,338)	(8,466)
Intangible Assets, net	$ 7,334	$ 7,254
Estimated useful life in years	11 years
Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Estimated useful life in years	11 years
Non-compete Agreements [Member]
Finite Lived Intangible Assets [Line Items]
Estimated useful life in years	5 years

Intangible Assets - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization expense	$ 900,000	$ 900,000	$ 900,000
Subsequent impairment of the underlying assets	0
Expected annual amortization expense for 2020	200,000
Expected annual amortization expense for 2021	200,000
Expected annual amortization expense for 2022	200,000
Expected annual amortization expense for 2023	200,000
Expected annual amortization expense for 2024	200,000
Expected annual amortization expense for 2025	200,000
Expected annual amortization expense for 2026	$ 200,000

Acquisition - Additional Information (Detail) - USD ($) $ in Thousands	Aug. 15, 2019	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Goodwill		$ 28,197	$ 27,808
ATP Containers LLC, dba TuffBox Container (“TuffBox”) [Member]
Business Acquisition [Line Items]
Total purchase price	$ 7,800
Intangible assets	1,300
Goodwill	400
ATP Containers LLC, dba TuffBox Container (“TuffBox”) [Member] \| Rental Equipment [Member]
Business Acquisition [Line Items]
Assets acquired	$ 5,500

Related Party Transactions - Additional Information (Detail) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Related Party Transactions [Abstract]
Amount due from (to) related party	$ 0	$ 0

Segment Reporting - Additional Information (Detail)	12 Months Ended
Segment Reporting - Additional Information (Detail)	Dec. 31, 2019 Segment Customer	Dec. 31, 2018 Customer	Dec. 31, 2017 Customer
Segment Reporting Information [Line Items]
Number of reportable segments \| Segment	4
Customer Concentration Risk [Member] \| Sales [Member]
Segment Reporting Information [Line Items]
Number of major customer \| Customer	0	0	0
Geographic Concentration Risk [Member] \| Sales [Member] \| Foreign Country Customers [Member]
Segment Reporting Information [Line Items]
Revenues from customers	5.00%	4.00%	4.00%

Segment Reporting - Summarized Financial Information for Company's Reportable Segments (Detail) - USD ($)
$ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2019

Sep. 30, 2019

Jun. 30, 2019

Mar. 31, 2019

Dec. 31, 2018

Sep. 30, 2018

Jun. 30, 2018

Mar. 31, 2018

Dec. 31, 2019

Dec. 31, 2018

Dec. 31, 2017

$ 92,231

$ 90,857

$ 88,105

$ 82,696

$ 85,091

$ 82,155

$ 77,267

$ 74,261

$ 353,889

$ 318,774

$ 289,417

101,038

82,907

78,068

115,303

96,649

94,549

147,221

173,562

127,439

122,008

133,115

143,147

116,983

105,085

570,230

498,330

462,034

80,391

73,139

69,908

70,997

78,282

59,881

57,005

65,103

64,050

53,928

50,170

266,165

233,251

206,345

124,793

115,770

111,605

38,248

46,748

29,066

27,310

35,166

35,824

24,449

22,042

141,372

117,481

94,740

12,331

(12,297)

(11,622)

35,454

43,455

25,965

24,251

32,018

32,553

21,106

19,018

129,125

104,695

83,452

170,018

134,098

98,107

128,099

121,016

128,099

121,016

105,872

1,520,411

1,416,000

1,520,411

1,416,000

1,347,533

967,500

$ 958,610

$ 943,152

$ 912,878

901,015

$ 888,607

$ 876,522

$ 865,338

967,500

901,015

862,320

Mobile Modular [Member]

182,316

159,136

142,584

69,395

54,696

50,448

49,299

40,742

38,234

301,010

254,574

231,266

22,071

21,200

21,247

143,618

120,750

103,935

65,699

58,017

55,583

77,919

62,733

48,352

7,946

(7,132)

(6,671)

69,973

55,601

41,681

75,433

63,374

34,526

83,182

72,295

83,182

72,295

59,274

868,807

817,375

868,807

817,375

775,400

610,048

572,032

$ 610,048

$ 572,032

$ 543,857

Utilization (period end)

^[1]

79.10%

79.30%

77.80%

Average utilization

^[1]

79.20%

78.20%

76.80%

TRS-RenTelco [Member]

$ 103,704

$ 89,937

$ 82,812

3,260

3,300

2,858

24,519

25,420

22,374

131,483

118,657

108,044

41,948

36,011

32,891

60,748

54,773

50,289

24,645

22,823

22,171

36,103

31,950

28,118

1,970

(2,696)

(2,320)

34,217

28,765

26,132

89,759

65,467

58,781

23,788

20,732

23,788

20,732

19,581

335,343

285,052

335,343

285,052

262,325

172,413

131,450

$ 172,413

$ 131,450

$ 109,482

Utilization (period end)

^[1]

64.50%

62.10%

61.70%

Average utilization

^[1]

66.20%

62.70%

62.90%

Adler Tanks [Member]

$ 67,869

$ 69,701

$ 64,021

28,383

24,911

24,762

1,671

1,441

2,572

97,923

96,053

91,355

16,372

15,928

15,770

47,014

48,055

43,218

29,321

30,026

29,542

17,693

18,029

13,676

3,436

(3,252)

(3,071)

14,257

14,777

10,605

4,826

5,257

4,800

17,281

19,992

17,281

19,992

18,663

316,261

313,573

316,261

313,573

309,808

185,039

197,533

$ 185,039

$ 197,533

$ 208,981

Utilization (period end)

^[1]

48.40%

56.40%

57.50%

Average utilization

^[1]

54.70%

59.90%

56.00%

Enviroplex [Member]

^[2]

$ 39,814

$ 29,046

$ 31,369

^[2]

39,814

29,046

31,369

^[2]

14,785

9,673

8,903

^[2]

5,128

4,904

4,309

^[2]

9,657

4,769

4,594

^[2]

(1,021)

783

440

^[2]

10,678

5,552

5,034

^[2]

$ 3,848

$ 7,997

$ 3,848

$ 7,997

$ 8,354

[1]	Utilization is calculated each month by dividing the cost of rental equipment on rent by the total cost of rental equipment excluding new equipment inventory and accessory equipment. The average utilization for the period is calculated using the average costs of rental equipment.
[2]	Gross Enviroplex sales revenues were $39,814, $30,407 and $31,369 in 2019, 2018 and 2017, respectively. There were $1,361 inter-segment sales to Mobile Modular in 2018, which have been eliminated in consolidation. There were no inter-segment sales in 2019 and 2017.

Segment Reporting - Summarized Financial Information for Company's Reportable Segments (Parenthetical) (Detail) - USD ($)

3 Months Ended

12 Months Ended

Dec. 31, 2019

Sep. 30, 2019

Jun. 30, 2019

Mar. 31, 2019

Dec. 31, 2018

Sep. 30, 2018

Jun. 30, 2018

Mar. 31, 2018

Dec. 31, 2019

Dec. 31, 2018

Dec. 31, 2017

$ 147,221,000

$ 173,562,000

$ 127,439,000

$ 122,008,000

$ 133,115,000

$ 143,147,000

$ 116,983,000

$ 105,085,000

$ 570,230,000

$ 498,330,000

$ 462,034,000

(115,303,000)

(96,649,000)

(94,549,000)

Sales [Member]

(110,229,000)

(92,618,000)

(91,500,000)

Enviroplex [Member]

^[1]

39,814,000

29,046,000

31,369,000

^[1]

(39,814,000)

(29,046,000)

(31,369,000)

Mobile Modular [Member]

301,010,000

254,574,000

231,266,000

Operating Segments [Member] | Enviroplex [Member] | Sales [Member]

(49,299,000)

(40,742,000)

(38,234,000)

Inter-segment Eliminations [Member]

39,814,000

30,407,000

31,369,000

Type of Revenue [Extensible List]

$ 0

us-gaap:ProductMember

Inter-segment Eliminations [Member] | Mobile Modular [Member]