WillScot (WSC) 10-K 26 Feb 21 2020 FY Annual report Financial data

Cover Page

Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2020	Feb. 22, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-37552
Entity Registrant Name	WILLSCOT MOBILE MINI HOLDINGS CORP.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-3430194
Entity Address, Address Line One	4646 E Van Buren St.
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	Phoenix
Entity Address, State or Province	AZ
Entity Address, Postal Zip Code	85008
City Area Code	480
Local Phone Number	894-6311
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	WSC
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
ICFR Auditor Attestation Flag	true
Entity Public Float			$ 715,019,406
Entity Common Stock, Shares Outstanding		229,046,278
Documents Incorporated by Reference	The information required by Part III of this Report, to the extent not set forth herein, is incorporated herein by reference from the registrant's definitive proxy statement relating to the Annual Meeting of Shareholders to be held in 2021, which definitive proxy statement will be filed with the Securities and Exchange Commission within 120 days after the end of the fiscal year to which this Report relates.
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Central Index Key	0001647088

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets
Cash and cash equivalents	$ 24,937	$ 3,045
Trade receivables, net of allowance for credit losses at December 31, 2020 and December 31, 2019 of $29,258 and $15,828, respectively	330,942	247,596
Inventories	21,655	15,387
Prepaid expenses and other current assets	29,954	14,621
Assets held for sale	12,004	11,939
Total current assets	419,492	292,588
Rental equipment, net	2,933,722	1,944,436
Property, plant and equipment, net	303,650	147,689
Operating lease assets	232,094	146,698
Goodwill	1,171,219	235,177
Intangible assets, net	495,947	126,625
Other non-current assets	16,081	4,436
Total long-term assets	5,152,713	2,605,061
Total assets	5,572,205	2,897,649
Liabilities and equity
Accounts payable	106,926	109,926
Accrued interest and liabilities	141,672	98,375
Deferred revenue and customer deposits	135,485	82,978
Operating lease liabilities - current	48,063	29,133
Current portion of long-term debt	16,521	0
Total current liabilities	448,667	320,412
Long-term debt	2,453,809	1,632,589
Deferred tax liabilities	307,541	70,693
Operating lease liabilities - non-current	183,761	118,429
Other non-current liabilities	37,150	46,571
Long-term liabilities	2,982,261	1,868,282
Total liabilities	3,430,928	2,188,694
Commitments and contingencies (see Note 18)
Preferred stock: $0.0001 par, 1,000,000 shares authorized and issued at September 30, 2018 and December 31, 2017, and 0 shares outstanding at June 30, 2018 and December 31, 2017	0	0
Common stock	23	0
Additional paid-in-capital	3,797,168	2,396,501
Accumulated other comprehensive loss	(37,207)	(62,775)
Accumulated deficit	(1,618,707)	(1,689,373)
Total shareholders' equity	2,141,277	644,365
Non-controlling interest	0	64,590
Total equity	2,141,277	708,955
Total liabilities and equity	5,572,205	2,897,649
Class A Common Stock
Liabilities and equity
Common stock	0	11
Class B Common Stock
Liabilities and equity
Common stock	$ 0	$ 1

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Trade receivables, allowance	$ 29,258	$ 15,828
Preferred share par value (in USD per share)	$ 0.0001	$ 0.0001
Preferred shares authorized (in shares)	1,000,000	1,000,000
Preferred shares issued (in shares)	0	0
Preferred shares outstanding (in shares)	0	0
Common stock par value (in USD per share)	$ 0.0001
Common stock authorized (in shares)	500,000,000
Common stock issued (in shares)	229,038,158
Common stock outstanding (in shares)	229,038,158
Class A Common Stock
Common stock par value (in USD per share)		$ 0.0001
Common stock authorized (in shares)		400,000,000
Common stock issued (in shares)		108,818,854
Common stock outstanding (in shares)		108,818,854
Class B Common Stock
Common stock par value (in USD per share)		$ 0.0001
Common stock authorized (in shares)		100,000,000
Common stock issued (in shares)		8,024,419
Common stock outstanding (in shares)		8,024,419

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues:
Leasing	$ 1,001,447	$ 744,185
Leasing			$ 518,235
Total revenues	1,367,645	1,063,665	751,412
Costs:
Modular leasing	227,376	213,151	143,120
Depreciation of rental equipment	200,581	174,679	121,436
Gross profit	659,973	413,313	289,384
Expenses:
Selling, general and administrative	360,626	271,004	234,820
Transaction costs	64,053	0	20,051
Other depreciation and amortization	43,249	12,395	13,304
Impairment losses on long-lived assets	0	2,848	1,600
Lease impairment expense and other related charges	4,876	8,674	0
Restructuring costs	6,527	3,755	15,468
Currency (gains) losses, net	(355)	(688)	2,454
Other income, net	(1,718)	(2,200)	(4,574)
Operating income	182,715	117,525	6,261
Interest expense	119,886	122,504	98,433
Loss on extinguishment of debt	42,401	8,755	0
Income (loss) before tax	20,428	(13,734)	(92,172)
Income tax benefit	(51,451)	(2,191)	(38,600)
Net income (loss)	71,879	(11,543)	(53,572)
Net income (loss) attributable to non-controlling interest, net of tax	1,213	(421)	(4,532)
Net income (loss) attributable to WillScot Mobile Mini	70,666	(11,122)	(49,040)
Non-cash deemed dividend related to warrant exchange	0	0	(2,135)
Net income (loss) attributable to WillScot Mobile Mini common shareholders	$ 70,666	$ (11,122)	$ (51,175)
Earnings (loss) per share attributable to WillScot Mobile Mini common shareholders:
Basic (in USD per share)	$ 0.42	$ (0.10)	$ (0.59)
Diluted (in USD per share)	$ 0.41	$ (0.10)	$ (0.59)
Weighted average shares:
Basic (in shares)	169,230,177	108,683,820	87,209,605
Diluted (in shares)	173,650,251	108,683,820	87,209,605
Delivery and installation
Revenues:
Revenues	$ 274,156	$ 220,057	$ 154,557
Costs:
Cost of sales	220,102	194,107	143,950
New units
Revenues:
Revenues	53,093	59,085	53,603
Total revenues	53,093	59,085	53,603
Costs:
Cost of sales	34,841	42,160	36,863
Rental units
Revenues:
Revenues	38,949	40,338	25,017
Total revenues	38,949	40,338	25,017
Costs:
Cost of sales	$ 24,772	$ 26,255	$ 16,659

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 71,879	$ (11,543)	$ (53,572)
Other comprehensive income (loss):
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	28,404	10,586	(11,639)
Net loss on derivatives, net of income tax benefit of $(539), $(1,471) and $(1,822) for the years ended December 31, 2020, 2019 and 2018, respectively	(1,749)	(4,809)	(5,955)
Total other comprehensive income (loss)	26,655	5,777	(17,594)
Comprehensive income (loss)	98,534	(5,766)	(71,166)
Comprehensive (loss) income attributable to non-controlling interest	(672)	105	(6,137)
Total comprehensive income (loss) attributable to WillScot Mobile Mini	$ 99,206	$ (5,871)	$ (65,029)

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustment, income tax expense (benefit)	$ (685)	$ 0	$ (161)
Net losses on derivatives, tax benefit	$ (539)	$ (1,471)	$ (1,822)

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Class A Common Stock	Class B Common Stock	Common StockClass A Common Stock	Common StockClass A Common StockCumulative Effect, Period of Adoption, Adjustment	Common StockClass B Common Stock	Common StockClass B Common StockCumulative Effect, Period of Adoption, Adjustment	Additional Paid-in Capital	Additional Paid-in CapitalCumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss)Cumulative Effect, Period of Adoption, Adjustment	Accumulated Deficit	Accumulated DeficitCumulative Effect, Period of Adoption, Adjustment	Total Shareholders' Equity	Total Shareholders' EquityCumulative Effect, Period of Adoption, Adjustment	Non-Controlling Interest	Non-Controlling InterestCumulative Effect, Period of Adoption, Adjustment
Beginning balance at Dec. 31, 2017	$ 484,550				$ 8		$ 1		$ 2,121,926		$ (49,497)		$ (1,636,819)		$ 435,619		$ 48,931
Beginning balance (in shares) at Dec. 31, 2017					84,645,000		8,024,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(53,572)												(49,040)		(49,040)		(4,532)
Other comprehensive income (loss)	(17,594)										(15,989)				(15,989)		(1,605)
Adoption of ASU 2018-02	0										(2,540)		2,540
Stock-based compensation	3,439								3,439						3,439
Issuance of Common Stock and contribution of proceeds to WSII	139,035				$ 1				131,460						131,461		7,574
Issuance of common stock and contribution of proceeds to WSII (in shares)					9,200,000
Acquisition transaction	148,108				$ 1				134,493						134,494		13,614
Acquisition transaction (in shares)					6,458,000
Common Stock issued in warrant exchange	(1,769)				$ 1				(1,770)						(1,769)
Common stock issued in warrant exchange (in shares)			8,206,000
Ending balance (in shares) at Dec. 31, 2018					108,509,000		8,024,000
Ending balance at Dec. 31, 2018	702,197				$ 11		$ 1		2,389,548		(68,026)		(1,683,319)		638,215		63,982
Ending balance (Accounting Standards Update 2014-09) at Dec. 31, 2018		$ 345				$ 0		$ 0		$ 0		$ 0		$ 345		$ 345		$ 0
Ending balance (Accounting Standards Update 2016-02) at Dec. 31, 2018		$ 5,226				$ 0		$ 0		$ 0		$ 0		$ 4,723		$ 4,723		$ 503
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(11,543)												(11,122)		(11,122)		(421)
Other comprehensive income (loss)	5,777										5,251				5,251		526
Issuance of Common Stock from the exercise of options and warrants	921				$ 0				921						921
Issuance of common stock from the exercise of options and warrants (in shares)					81,000
Stock-based compensation and issuance of Common Stock from vesting	$ 6,032				$ 0				6,032						6,032
Stock-based compensation and issuance of Common Stock from vesting (in shares)	309,857				229,000
Ending balance (in shares) at Dec. 31, 2019			108,818,854	8,024,419	108,819,000		8,024,000
Ending balance at Dec. 31, 2019	$ 708,955				$ 11		$ 1		2,396,501		(62,775)		(1,689,373)		644,365		64,590
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	71,879												70,666		70,666		1,213
Other comprehensive income (loss)	26,655										28,540				28,540		(1,885)
Acquisition transaction	1,348,630				$ 11				1,348,619						1,348,630
Acquisition transaction (in shares)					106,427,000
Sapphire Exchange - See Note 12 (in shares)					10,641,000		(8,024,000)
Sapphire Exchange - See Note 12	0				$ 1		$ (1)		66,890		(2,972)				63,918		(63,918)
Issuance of Common Stock from the exercise of options and warrants	10,616				$ 0				10,616						10,616
Issuance of common stock from the exercise of options and warrants (in shares)					2,836,000
Repurchase and cancellation of options and warrants	(21,864)								(21,864)						(21,864)
Withholding taxes on net share settlement of stock-based compensation and option exercises	(13,473)								(13,473)						(13,473)
Stock-based compensation and issuance of Common Stock from vesting	$ 9,879								9,879						9,879
Stock-based compensation and issuance of Common Stock from vesting (in shares)	13,792,582				315,000
Ending balance (in shares) at Dec. 31, 2020	229,038,158				229,038,000		0
Ending balance at Dec. 31, 2020	$ 2,141,277				$ 23		$ 0		$ 3,797,168		$ (37,207)		$ (1,618,707)		$ 2,141,277		$ 0

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities:
Net income (loss)	$ 71,879	$ (11,543)	$ (53,572)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	246,948	189,436	136,467
Provision for credit losses	32,593	14,496	7,656
Impairment losses on long-lived assets	0	2,848	1,600
Impairment losses on right of use assets	57	4,160
Gain on sale of rental equipment and other property, plant and equipment	(14,124)	(11,660)	(12,878)
Amortization of debt discounts and debt issuance costs	13,085	11,450	7,652
Loss on extinguishment of debt	42,401	8,755	0
Stock-based compensation expense	9,879	6,686	3,439
Deferred income tax benefit	(55,155)	(2,624)	(40,192)
Unrealized currency losses (gains), net	424	(745)	1,982
Changes in operating assets and liabilities, net of effect of businesses acquired:
Trade receivables	(26,723)	(63,648)	(36,452)
Inventories	2,775	869	(1,241)
Prepaid and other assets	(4,547)	8,237	8,416
Operating lease assets and liabilities	789	(438)	0
Accrued interest	(11,877)	(4,217)	17,526
Accounts payable and other accrued liabilities	(16,046)	4,865	(14,462)
Deferred revenue and customer deposits	12,454	15,639	11,208
Net cash provided by operating activities	304,812	172,566	37,149
Investing activities:
Acquisition of a businesses, net of cash acquired	17,173	0	(1,083,146)
Proceeds from sale of rental equipment	38,949	42,101	30,761
Purchase of rental equipment and refurbishments	(172,383)	(205,106)	(160,883)
Proceeds from the sale of property, plant and equipment	7,355	18,763	688
Purchase of property, plant and equipment	(16,454)	(8,340)	(4,622)
Net cash used in investing activities	(125,360)	(152,582)	(1,217,202)
Financing activities:
Receipts from issuance of Common Stock from the exercise of options and warrants	10,616	921	147,201
Repurchase and cancellation of warrants	(21,777)	0	0
Payment of Common Stock issuance costs	(4,222)	0	0
Receipts from borrowings	2,786,793	552,230	1,212,629
Payment of financing costs	(65,475)	(2,623)	(36,579)
Repayment of borrowings	(2,808,370)	(568,686)	(143,094)
Payment of debt extinguishment premium costs	(34,610)	(7,152)	0
Principal payments on finance lease obligations	(8,440)	(99)
Principal payments on finance lease obligations			(120)
Taxes paid on employee stock awards	(13,473)	(654)	0
Net cash (used in) provided by financing activities	(158,958)	(26,063)	1,180,037
Effect of exchange rate changes on cash and cash equivalents	1,398	166	(211)
Net change in cash and cash equivalents	21,892	(5,913)	(227)
Cash and cash equivalents at the beginning of the year	3,045	8,958	9,185
Cash and cash equivalents at the end of the year	24,937	3,045	8,958
Supplemental cash flow information:
Interest paid	108,740	115,582	51,986
Income taxes paid (refunded), net	4,234	(1,148)	2,617
Capital expenditures accrued or payable	23,553	23,946	20,785
Non-cash deemed dividend related to warrant exchange	0	0	2,135
Non-cash acquisition of a business	$ 0	$ 0	$ 148,108

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Organization and Nature of Operations WillScot Mobile Mini Holdings Corp. (“WillScot Mobile Mini” and, together with its subsidiaries, the “Company”) is a leading provider of modular space and portable storage solutions in the United States (“US”), Canada, Mexico and the United Kingdom ("UK"). The Company also maintains a fleet of specialty containment products, including liquid and solid containment solutions. The Company leases, sells, delivers and installs mobile solutions and storage products through an integrated network of branch locations that spans North America and the UK. WillScot Corporation, a Delaware corporation (“WillScot”) entered into an Agreement and Plan of Merger, dated as of March 1, 2020, as amended on May 28, 2020 (as so amended, the “Merger Agreement”), by and among WillScot, Mobile Mini, Inc. (“Mobile Mini”), and Picasso Merger Sub, Inc., a wholly-owned subsidiary of WillScot (“Merger Sub”). On July 1, 2020, Merger Sub merged with and into Mobile Mini (the “Merger”). At the effective time of the Merger, the separate corporate existence of Merger Sub ceased, and Mobile Mini continued its existence as the surviving corporation in the Merger and a wholly-owned subsidiary of WillScot. As a result of the Merger, each issued and outstanding share of Mobile Mini Common Stock, par value $0.01 per share (other than treasury shares held by Mobile Mini), was converted automatically into the right to receive 2.405 shares of WillScot’s Class A Common Stock, par value $0.0001 per share (the “WillScot Class A Common Stock”), and cash in lieu of any fractional shares. Immediately following the Merger, WillScot changed its name to “WillScot Mobile Mini Holdings Corp.” and filed an amended and restated certificate of incorporation (the “A&R Charter”), which reclassified all outstanding shares of WillScot Class A Common Stock and converted such shares into shares of Common Stock, par value $0.0001 per share, of WillScot Mobile Mini (“WillScot Mobile Mini Common Stock”). The WillScot Class A Common Stock was listed on the Nasdaq Capital Market (Nasdaq: WSC) up until the Merger, and the WillScot Mobile Mini Common Stock has been listed on the Nasdaq Capital Market (Nasdaq: WSC) since the Merger. As used herein, the term “Common Stock” or “the Company’s Common Stock” refers to WillScot Class A Common Stock prior to filing of the A&R Charter on July 1, 2020 and to WillScot Mobile Mini Common Stock as of and following the filing of the A&R Charter July 1, 2020. As the Merger closed on July 1, 2020 the preparation of financial statements in accordance with US Generally Accepted Accounting Principles (“GAAP”) requires that our consolidated financial statements and most of the disclosures in these Notes be presented on a historical basis. Unless the context otherwise requires, the terms “Company” and “WillScot Mobile Mini” as used in these financial statements mean WillScot and its subsidiaries when referring to periods prior to July 1, 2020 (prior to the Merger) and to WillScot Mobile Mini, when referring to periods on or after July 1, 2020 (after the Merger). Basis of Presentation The consolidated financial statements were prepared in conformity with GAAP. Principles of Consolidation The consolidated financial statements comprise the financial statements of WillScot Mobile Mini and its subsidiaries that it controls due to ownership of a majority voting interest. Subsidiaries are fully consolidated from the date of acquisition, being the date on which the Company obtains control, and continue to be consolidated until the date when such control ceases. The financial statements of the subsidiaries are prepared for the same reporting period as WillScot Mobile Mini. All intercompany balances and transactions are eliminated. Accounting Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in these consolidated financial statements and accompanying notes. Actual results could differ from those estimates. Cash and Cash Equivalents The Company considers all highly liquid instruments with a maturity of three months or less when purchased to be cash equivalents. Trade Receivables and Allowance for Credit Losses The Company is exposed to credit losses from trade receivables generated through its leasing and sales business. The Company assesses each customer’s ability to pay for the products it leases or sells by conducting a credit review. The credit review considers expected billing exposure and timing for payment and the customer’s established credit rating. The Company performs its credit review of new customers at inception of the customer relationship and for existing customers when the customer transacts new leases after a defined period of dormancy. The Company also considers contract terms and conditions, country risk and business strategy in the evaluation. The Company monitors ongoing credit exposure through an active review of customer balances against contract terms and due dates. The Company may employ collection agencies and legal counsel to pursue recovery of defaulted receivables. The allowances for credit losses reflect the estimate of the amount of receivables that the Company will be unable to collect based on historical write-off experience and, as applicable, current conditions and reasonable and supportable forecasts that affect collectability. This estimate could require change based on changing circumstances, including changes in the economy or in the particular circumstances of individual customers. Accordingly, the Company may be required to increase or decrease our allowances. In accordance with the adoption of Accounting Standards Update ("ASU") 2016-2, Leases (Topic 842) (" ASC 842"), effective January 1, 2019, and the adoption of ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) ("ASC 326"), effective January 1, 2020, specifically identifiable lease revenue receivables and sales receivables not deemed probable of collection are recorded as a reduction of revenue. The remaining provision for credit losses is recorded as selling, general and administrative expense. For the year ended December 31, 2018, the entire provision for credit losses was recorded as a selling, general and administrative expense. The Company reviews the adequacy of the allowance on a quarterly basis. Activity in the allowance for credit losses for the years ended December 31 was as follows: (in thousands) 2020 2019 2018 Balance at beginning of year $ 15,828 $ 9,340 $ 4,845 Provision for credit losses, net of recoveries (a) 31,386 14,496 7,656 Write-offs (18,034) (7,945) (3,089) Foreign currency translation and other 78 (63) (72) Balance at end of period $ 29,258 $ 15,828 $ 9,340 (a) For the years ended December 31, 2020 and 2019, the provision for credit losses includes $18.0 million and $10.0 million, respectively, recorded as a reduction to revenue for the provision of specific receivables whose collection is not considered probable. Concentration of Credit Risk The Company’s trade accounts receivable subject the Company to potential concentrations of credit risk. The Company performs on-going credit evaluations of its customers. Receivables related to sales are generally secured by the product sold to the customer. The Company generally has the right to repossess its rental units in the event of non-payment of receivables relating to the Company’s leasing operations. The Company’s large number of customers in diverse geographic areas and end markets mitigates the concentration of credit risk. No single customer accounted for more tha n 1.2% and 1.5% of the Company’s receivables at December 31, 2020 and 2019, respectively. The Company’s top five customers accounted for 4.9% and 4.1% of the receivables at December 31, 2020 and 2019, respectively. Inventories Inventories consist of raw materials, supplies, and finished units. Inventories are measured at the lower of cost or net realizable value based on the weighted-average cost. The cost includes expenditures incurred in acquiring the inventories, production or conversion costs, and other costs incurred in bringing them to their existing location and condition. Rental Equipment Rental equipment is comprised of modular space and portable storage units held for rent or on rent to customers, tank and pump solutions products, which consist primarily of liquid and solid containment units, pumps and filtration equipment, and value-added products and services (“VAPS”) which are in use or available to be used by customers. Rental equipment is measured at cost less accumulated depreciation and impairment losses. Cost includes expenditures that are directly attributable to the acquisition of the asset. Costs of improvements and betterments to rental equipment are capitalized when such costs extend the useful life of the equipment or increase the rental value of the unit. Costs incurred for equipment to meet a particular customer specification are capitalized and depreciated over the lease term taking in consideration the residual value of the asset. Maintenance and repair costs are expensed as incurred. Depreciation is generally computed using the straight-line method over estimated useful lives, as follows: Estimated Useful Life Residual Value Modular space units 10 - 20 years 20 - 50% Portable storage units 30 years 55% Tank and pump equipment 7 - 25 years —% VAPS and other related rental equipment 1 - 8 years —% Property, Plant and Equipment Property, plant and equipment is measured at cost less accumulated depreciation and impairment losses. The Company capitalizes external costs and directly attributable internal costs to acquire or create internal use software incurred subsequent to the completion of the preliminary project stage. Costs associated with post-implementation activities are expensed as incurred. The Company evaluates implementation costs incurred in a cloud computing arrangement that is a service contract as described in Cloud Computing Arrangements below. Land is not depreciated. Leasehold improvements are amortized over the shorter of 15 years or the lease term. Assets leased under capital leases are depreciated over the shorter of the lease term or their useful life, unless it is reasonably certain that the Company will obtain ownership by the end of the lease term. Maintenance and repair costs are expensed as incurred. Depreciation is generally computed using the straight-line method over estimated useful lives as follows: Estimated Useful Life Buildings and leasehold improvements 10 - 40 years (a) Vehicles, machinery, and equipment 3 - 30 years Furniture and fixtures 3 - 10 years Software 3 - 10 years (a) Improvements to leased properties are depreciated over the lesser of the estimated useful life of the asset or the remaining term of the respective lease. Held for Sale Property, plant and equipment to be sold is classified as held for sale in the period in which: (i) the Company has approved and committed to a plan to sell the asset, (ii) the asset is available for immediate sale in its present condition, (iii) an active program to locate a buyer and other actions required to sell the asset have been initiated, (iv) the sale of the asset is probable, (v) the asset is being actively marketed for sale at a price that is reasonable in relation to its current fair value, and (vi) it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. Assets held for sale are initially measured at the lower of the carrying value or the fair value less cost to sell. Losses resulting from this measurement are recognized in the period in which the held for sale criteria are met while gains are not recognized until the date of sale. Once designated as held for sale, the Company stops recording depreciation expense on the asset. The Company assesses the fair value less cost to sell of long-lived assets held for sale at each reporting period until the assets no longer meet this classification. Impairment of Long-Lived Assets When circumstances indicate the carrying amount of long-lived assets in a held-for-use asset group may not be recoverable, the Company evaluates the assets for potential impairment using internal projections of undiscounted cash flows resulting from the use and eventual disposal of the assets. Events or changes in circumstances that may necessitate a recoverability evaluation include, but are not limited to, adverse changes in the regulatory environment or an expectation it is more likely than not that the asset will be disposed of before the end of its previously estimated useful life. If the carrying amount of the assets exceeds the undiscounted cash flows, an impairment expense is recognized for the amount by which the carrying amount of the asset group exceeds its fair value (subject to the carrying amount not being reduced below fair value for any individual long-lived asset that is determinable without undue cost and effort). Consistent with the provisions of ASC 842, the Company assesses whether any operating lease as set impairment exists in accordance with the measurement guidance in Accounting Standard Codification ("ASC") 360, Property Plant and Equipment . Cloud Computing Arrangements In accordance with ASU 2018-15, Goodwill and Other – Internal-Use Software (Subtopic 350-40) (“ASC 350-40"), t he Company evaluates implementation costs incurred in a cloud computing arrangement that is a service contract under the internal-use software framework. Costs related to preliminary project activities and post implementation activities are expensed as incurred. Costs incurred in the development stage are generally capitalized as other assets. Amortization expense is calculated on a straight-line basis over the contractual term of the cloud computing arrangement and recorded as selling, general and administrative expense. Capitalized implementation costs for cloud computing arrangements totale d $4.0 million a t December 31, 2020. The comparative financial statement information has not been restated and continues to be reported under the accounting standards in effect for those periods. The adoption of the guidance did not have a material impact on the Company's consolidated balance sheet as of January 1, 2020. Goodwill and Goodwill Impairment For acquired businesses, the Company records assets acquired and liabilities assumed at their estimated fair values on the respective acquisition dates. Based on these values, the excess purchase price over the fair value of the net assets acquired is recorded as goodwill. Generally, reporting units are at the operating segment level or one level below the operating segment (the component level), if discrete financial information is prepared and regularly reviewed by segment management. Goodwill acquired in a business combination is assigned to each of the Company’s reporting units that are expected to benefit from the combination. The Company performs its annual impairment test of goodwill as of October 1 at the reporting unit level, as well as during any reporting period in which events or changes in circumstances occur that, in management’s judgment, may constitute triggering events under ASC 350-20, Intangibles – Goodwill and Other, Testing Goodwill for Impairment . The Company performs its assessment of goodwill utilizing either a qualitative or quantitative impairment test. The qualitative impairment test assesses company-specific, industry, market and general economic factors to determine whether it is more likely than not that the fair value of the reporting unit is less than its carrying amount. If the Company concludes that it is more likely than not that the fair value of the reporting unit is less than its carrying amount, or elects not to use the qualitative impairment test, a quantitative impairment test is performed. The quantitative impairment test involves a comparison of the estimated fair value of a reporting unit to its carrying amount. The Company uses an independent valuation specialist for its annual impairment tests to assist in the valuation. The Company has historically used the quantitative impairment test to evaluate goodwill for impairment. The Company used the qualitative approach for the reporting units acquired in the Merger due to the proximity of the July 1, 2020 acquisition date to the October 1, 2020 measurement date. Determining the fair value of a reporting unit is judgmental in nature and involves the use of significant estimates and assumptions. These estimates and assumptions include revenue growth rates and operating margins used to calculate projected future cash flows, risk-adjusted discount rates, value of net operating losses, future economic and market conditions and determination of appropriate market comparables. Management bases fair value estimates on assumptions it believes to be reasonable but that are unpredictable and inherently uncertain. Actual future results may differ from these estimates. If the carrying amount of the reporting unit exceeds the calculated fair value of the reporting unit, an impairment charge would be recognized for the excess, not to exceed the amount of goodwill allocated to that reporting unit. Intangible Assets Other than Goodwill Intangible assets that are acquired by the Company and determined to have an indefinite useful life are not amortized but are tested for impairment at least annually. The Company’s indefinite-lived intangible assets consist of the Williams Scotsman trade name and the Mobile Mini trade name. The Company performs its assessment of indefinite-lived intangible assets utilizing either a qualitative or quantitative impairment test. When utilizing a quantitative impairment test, the Company calculates fair value using a relief-from-royalty method. This method is used to estimate the cost savings that accrue to the owner of an intangible asset who would otherwise have to pay royalties or license fees on revenues earned through the use of the asset. If the carrying amount of the indefinite-lived intangible asset exceeds its fair value, an impairment charge would be recorded to the extent the recorded indefinite-lived intangible asset exceeds the fair value. Other intangible assets that have finite useful lives are measured at cost less accumulated amortization and impairment losses, if any. Amortization is recognized in profit or loss over the estimated useful lives of the intangible asset. Purchase Accounting The Company accounts for acquisitions of businesses under the acquisition method. Under the acquisition method of accounting, the Company records assets acquired and liabilities assumed at their estimated fair value on the date of acquisition. Goodwill is measured as the excess of the fair value of the consideration transferred over the fair value of the identifiable net assets. Estimated fair values of acquired assets and liabilities are provisional and could change as additional information is received. When appropriate, our estimates of the fair values of assets and liabilities acquired include assistance from independent third-party valuation firms. Valuations are finalized as soon as practicable, but not later than one year from the acquisition date. Any subsequent changes to purchase price allocations result in a corresponding adjustment to goodwill. Long-lived assets (principally rental equipment), goodwill and other intangible assets generally represent the largest components of our acquisitions. Rental equipment is valued utilizing a replacement cost approach. Intangible assets are recognized at their estimated fair values as of the date of acquisition and generally consist of customer relationships and trade names. Determination of the estimated fair value of intangible assets requires judgment. The estimated fair value of customer relationships is determined based on estimates and judgments regarding discounted future after-tax earnings and cash flows arising from lease renewals and new lease arrangements expected from customer relationships. The fair value of trade name intangible assets is determined utilizing the relief from royalty method. Under this form of the income approach, a royalty rate based on observed market royalties is applied to projected revenue supporting the trade name and discounted to present value. Debt Issuance Costs Debt issuance costs are recorded as direct deductions to the corresponding debt in long-term debt on the consolidated balance sheets. If no amounts are outstanding under the Company’s credit agreement as of a period end, the related debt issuance costs are recorded in other non-current assets in the consolidated balance sheets. Debt issuance costs are deferred and amortized to interest expense over the term of the respective debt using the effective interest method or straight-line interest method as appropriate. Retirement Benefit Obligation The Company provides benefits to certain of its employees under defined contribution benefit plans. The Company’s contributions to these plans are generally based on a percentage of employee compensation or employee contributions. These plans are funded on a current basis. For its US and Canada employees, the Company sponsors defined contribution benefit plans that have discretionary matching contribution and profit-sharing features. Fo r the years ended December 31, 2020, 2019 and 2018, the Company made matc hing contributions of $7.1 million, $5.4 million and $3.8 million to these plans, respectively. Stock-Based Compensation Prior to the Merger, stock awards were granted under the WillScot Corporation 2017 Incentive Award Plan (the "2017 Incentive Plan"), which included Restricted Stock Awards ("RSAs") and Restricted Stock Units ("RSUs"). On June 24, 2020, WillScot's stockholders approved the WillScot Mobile Mini 2020 Incentive Award Plan ("2020 Incentive Plan") to take effect pending completion of the Merger. The plan amended and restated in its entirety the 2017 Incentive Plan. As a result, all historical and future incentive awards to the Company's Board of Directors, executive officers and employees, as determined by the Company's Compensation Committee ("the Comp Committee"), are granted under the 2020 Incentive Plan. The 2020 Incentive Plan is administered by the Comp Committee. Under the 2020 Incentive Plan, the Comp Committee may grant an aggreg ate of 6,488,988 shares of Common Stock in the form of non-qualified stock options, incentive stock options, stock appreciation rights, RSAs, RSUs, performance compensation awards and stock bonus awards. Stock-based payments, including the grant of stock options, RSAs and RSUs, are subject to service-based vesting requirements, and expense is recognized on a straight-line basis over the vesting period. Forfeitures are accounted for as they occur. Stock-based compensation expense includes grants of stock options, time-based RSUs ("Time-Based RSUs") and performance-based RSUs ("Performance-Based RSUs", together with Time-Based RSUs, the "RSUs"). The 2020 Incentive Plan continues the former Market-Based RSUs renamed as "Performance-Based RSUs." RSUs are recognized in the financial statements based on their fair value. In addition, stock-based payments to non-executive directors include grants of RSAs. Time-Based RSUs and RSAs are valued based on the intrinsic value of the difference between the exercise price, if any, of the award and the fair market value of WillScot Mobile Mini's Common Stock on the grant date. Performance-Based RSUs are valued based on a Monte Carlo simulation model to reflect the impact of the Performance-Based RSUs market condition. The probability of satisfying a market condition is considered in the estimation of the grant-date fair value for Performance-Based RSUs and the compensation cost is not reversed if the market condition is not achieved, provided the requisite service has been provided. RSAs cliff vest in a one year period. Time-Based RSUs vest ratably over a period of four years. Performance-Based RSUs cliff vest based on achievement of the relative total stockholder return ("TSR") of the Company's Common Stock as compared to the TSR of the constituents of the Russell 3000 Index at the grant date over the performance period of three years. The target number of RSUs may be adjusted from 0% to 150% based on the TSR attainment levels defined by the Comp Committee. The 100% target payout is tied to performance at the 50% percentile, with a payout curve ranging from 0% (for performance less than the 25% percentile) to 150% (for performance at or above the 75% percentile). Vesting is also subject to continued service requirements through the vesting date. Stock options vest in tranches over a period of four years and expire ten years from the grant date. The fair value of each stock option award on the grant date is estimated using the Black-Scholes option-pricing model with the following assumptions: expected dividend yield, expected stock price volatility, weighted-average risk-free interest rate and weighted-average expected term of the options. The volatility assumption used in the Black-Scholes option-pricing model was based on a blend of peer group volatility and Company trading history as the Company did not have a sufficient trading history as a stand-alone public company. Future calculations will use the Company trading history. Additionally, due to an insufficient history with respect to stock option activity and post-vesting cancellations, the expected term assumption is based on the simplified method under GAAP, which is based on the vesting period and contractual term for each tranche of awards. The mid-point between the weighted-average vesting term and the expiration date is used as the expected term under this method. The risk-free interest rate used in the Black-Scholes model is based on the implied US Treasury bill yield curve at the date of grant with a remaining term equal to the Company’s expected term assumption. WillScot Mobile Mini has never declared or paid a cash dividend on common shares. Foreign Currency Translation and Transactions The Company’s reporting currency is the US Dollar (“USD”). Exchange rate adjustments resulting from foreign currency transactions are recognized in profit or loss, whereas effects resulting from the translation of financial statements are reflected as a component of accumulated other comprehensive loss, which is a component of shareholders’ equity. The assets and liabilities of subsidiaries whose functional currency is different from the USD are translated into USD at exchange rates at the reporting date and income and expenses are translated using average exchange rates for the respective period. Exchange rate adjustments resulting from transactions in foreign currencies (currencies other than the Company entities’ functional currencies) are remeasured to the respective functional currencies using exchange rates at the dates of the transactions and are recognized in currency (gains) losses on the consolidated statements of operations. Foreign exchange gains and losses arising from a receivable or payable to a consolidated Company entity, the settlement of which is neither planned nor anticipated in the foreseeable future, are considered to form part of a net investment in the Company entity and are included within accumulated other comprehensive loss. Derivative Instruments and Hedging Activities The Company utilizes derivative financial instruments, specifically interest rate swaps, to manage its exposure to fluctuations in interest rates on variable rate debt. The Company does not use derivatives for trading or speculative purposes. The Company records derivatives on the balance sheet at fair value within prepaid expenses and other current assets and other non-current assets (if in an unrealized gain position) or within accrued liabilities and other non-current liabilities (if in an unrealized loss position). If a derivative is designated as a cash flow hedge and meets the highly effective threshold, the changes in the fair value of derivatives are recorded in accumulated other comprehensive income (loss). Amounts reported in accumulated other comprehensive income (loss) related to the cash flow hedges are reclassified to earnings within interest expense when the hedged item impacts earnings. For any derivative instruments not designated as hedging instruments, changes in fair value would be recognized in earnings within interest expense in the period that the change occurs. Cash flows from derivative instruments are presented within net cash provided by operating activities in the consolidated statements of cash flows. The Company assesses, both at the inception of the hedge and on an ongoing quarterly basis, whether the derivatives designated as cash flow hedges are highly effective in offsetting the changes in cash flows of the hedged items. The use of derivative financial instruments carries certain risks, including the risk that the counterparties to these contractual arrangements are not able to perform under the agreements. To mitigate this risk, the Company enters into derivative financial ins truments only with counterparties with high credit ratings and with major financial institutions. The Company does not anticipate that any of the counterparties will fail to meet their obligations. Revenue Recognition A performance obligation is a promise in a contract to transfer a distinct good or service to the customer. A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. Leasing and Services Revenue The majority of revenue is generated by rental income subject to the guidance of ASC 840, Leases ("ASC 840") in 2018 and ASC 842 in 2019 and 2020. The remaining revenue is generated by performance obligations in contracts with customers for services or sale of units subject to the guidance in ASC 605, Revenue ("ASC 605"), in 2018 and Accounting Standards Update ("ASU") 2014-09, Revenue from Contracts with Customers (Topic 606) ("ASC 606") in 2019 and 2020. Leasing Revenue Income from operating leases is recognized on a straight-line basis over the lease term. The Company's lease arrangements can include multiple lease and non-lease components. Examples of lease components include, but are not limited to, the lease of modular space, portable storage units and VAPS. Examples of non-lease components include, but are not limited to, the delivery, install ation, maintenance, and removal services commonly provided in a bundled transaction with the lease components. Arrangement consideration is allocated between lease deliverables and non-lease components based on the relative estimated selling (leasing) price of each deliverable. Estimated selling (leasing) price of the lease deliverables is based upon the estimated stand-alone selling price of the related performance obligations using an adjusted market approach. When leases and services are billed in advance, recognition of revenue is deferred until services are rendered. If equipment is returned prior to the contractually obligated period, the excess, if any, between the amount the customer is contractually required to pay over the cumulative amount of revenue recognized to date is recognized as incremental revenue upon return. Rental equipment is leased primarily under operating leases and, from time to time, under sales-type lease arrangements. Operating lease minimum contractual terms within the NA Modular segment, as defined in Note 19, generally range from 1 month to 60 months and averaged approximately 9 months across this segment's rental fleet for the year ended December 31, 2020. Rental contracts with customers within the NA Storage and UK Storage segments are generally based on a 28-day rate and billing cycle. The rental continues until cancelled by the Company or the customer. T here were no material sales-type lease arrangements as of December 31, 2020 or 2019. The Company may use third parties to satisfy its performance obligations, including both the provision of rental units and other services. To determine whether it is the principal or agent in the arrangement, the Company reviews each third-party relationship on a contract-by-contract basis. The Company is considered an agent when its role is to arrange for another entity to provide the rental units and other services to the customer. In these instances, the Company does not control the renta

Business Combinations and Acqui

Business Combinations and Acquisitions	12 Months Ended
	Dec. 31, 2020
Business Combinations [Abstract]
Business Combinations and Acquisitions	Business Combinations and Acquisitions Tyson Acquisition On January 3, 2018, the Company acquired all of the issued and outstanding membership interests of Onsite Space LLC, d/b/a Tyson Onsite (“Tyson”) for $24.0 million in cash consideration, net of cash acquired. ModSpace Acquisition On August 15, 2018, the Company acquired Modular Space Holdings, Inc. ("ModSpace"), a privately-owned national provider of modular and portable storage units. Purchase Price The aggregate purchase price for ModSpace was $1.2 billion and consisted of (i) $1.1 billion in cash, (ii) 6,458,229 shares of WillScot's Class A Common Stock (the "Stock Consideration") with a fair market value of $95.8 million, (iii) warrants to purchase an aggregate of 10,000,000 shares of WillScot’s Class A Common Stock at an exercise price of $15.50 per share (the "2018 Warrants") with a fair market value of $52.3 million, and (iv) a working capital adjustment of $4.7 million. The acquisition was funded by the net proceeds of WillScot's issuance of 9,200,000 shares of Class A Common Stock, the net proceeds of the issuance of $300.0 million in senior secured notes and $200.0 million in unsecured notes, and borrowings under the ABL Facility. As of the date of acquisition, the fair market values of the Stock Consideration and 2018 Warrants were $14.83 per share and $5.23 per warrant, respectively, with the warrant values determined using a Black-Scholes valuation model. The fair market v alue of the Class A shares was determined utilizing the $15.78 per share closing price of the Company's shares on August 15, 2018, discounted by 6.0%, to reflect a lack of marketability based on the lock-up restrictions contemplated by the merger agreement. The estimated fair values of the Stock Consideration and 2018 Warrants are Level 3 fair value measurements, as defined in Note 15. The fair value of each share and warrant was estimated using the Black-Scholes model. The following table summarizes the key inputs utilized to determine the fair value of the Stock Consideration and 2018 Warrants included within the purchase price of ModSpace. Stock Consideration 2018 Warrants fair value inputs Expected volatility 28.6 % 35.0 % Risk-free rate of interest 2.2 % 2.7 % Dividend Yield — % — % Expected life (years) 0.5 4.3 Pro Forma Information The unaudited pro forma information below has been prepared using the purchase method of accounting, giving effect to the ModSpace acquisition as if it had been completed on January 1, 2018. The pro forma information is not necessarily indicative of the Company’s results of operations had the acquisition been completed on the above date, nor is it necessarily indicative of the Company’s future results. The pro forma information does not reflect any cost savings from operating efficiencies or synergies that could result from the acquisition, and also does not reflect additional revenue opportunities following the acquisition. (unaudited, in thousands) Year Ended December 31, 2018 (a) WillScot revenues $ 751,412 ModSpace revenues 312,609 Pro forma revenues $ 1,064,021 WillScot loss from operations before income tax $ (92,172) ModSpace loss from operations before income tax (7,457) Loss from operations before income tax before pro forma adjustments (99,629) Pro forma adjustments to combined loss from operations before income tax: Impact of fair value adjustments/useful life changes on depreciation 10,135 Intangible asset amortization (625) (b) Interest expense (41,178) (c) Elimination of ModSpace interest 20,279 (d) Pro forma loss from operations before income tax (111,018) (e) Income tax benefit (43,462) (f) Pro forma net loss $ (67,556) (a) Pro forma results for the year ended December 31, 2018 include ModSpace historical activity. Post-acquisition ModSpace revenues and pre-tax income are reflected in the Company's historical revenue and pre-tax income amounts. (b) Amortization of the trade names acquired. The ModSpace trade name was assigned a value of $3.0 million and a life of three years. (c) In connection with the ModSpace acquisition, the Company drew an incremental $419.0 million on the ABL Facility and issued $300.0 million of 2023 Secured Notes and $200.0 million of unsecured notes. An interest rate of 6.54% was used to calculate pro forma interest expense as a result of the ModSpace acquisition, which represents the weighted-average interest rate for the aforementioned borrowings at December 31, 2018. Interest expense includes amortization of related deferred financing fees on debt incurred in conjunction with the ModSpace acquisition. (d) Interest on ModSpace historical debt was eliminated. (e) Pro forma loss from operations before income taxes includes $15.5 million of restructuring expense, $30.0 million of integration costs, and $20.1 million of transaction costs incurred by WillScot for the year ended December 31, 2018. Additionally, pro forma pre-tax loss for the year ended December 31, 2018 also includes $20.5 million of interest expense associated with bridge financing fees incurred in connection with the acquisition of ModSpace. (f) As the combined pro forma company was in a tax loss position in 2018, all pro forma adjustments for US tax effects are at the federal and state US statutory tax rate of 25.8% since the adjustments represent future deductible or taxable temporary differences. Mobile Mini Merger On March 1, 2020, the Company, along with its newly formed subsidiary, Merger Sub, entered into the Merger Agreement with Mobile Mini, hereby referred to as the “Merger”. The Merger was completed on July 1, 2020 and Merger Sub merged with and into Mobile Mini and the separate corporate existence of Merger Sub ceased, and Mobile Mini continued its existence as the surviving corporation in the Merger and a wholly-owned subsidiary of the Company. Mobile Mini is a leading provider of portable storage solutions in North America and the UK and a leading provider of specialty containment solutions in the US. Purchase Price Upon completion of the Merger, each issued and outstanding share of Mobile Mini Common Stock, par value $0.01 per share, converted to 2.405 shares of WillScot Class A Common Stock, par value $0.0001 per share, and cash in lieu of any fractional shares. The Company issued 106,426,721 shares of Class A Common Stock to Mobile Mini stockholders as consideration for the Merger. The trading price of the Class A Common Stock was $12.53 per share on the closing date. In addition, Mobile Mini stock options converted into WillScot Mobile Mini stock options. The purchase price has been determined to be as follows: (in thousands, except share and per share data) Mobile Mini Common Stock outstanding 44,252,275 Share conversion ratio 2.405 Common Stock issued 106,426,721 Common Stock per share price as of July 1, 2020 $ 12.53 Fair value of shares of WillScot Class A Common Stock issued $ 1,333,527 Cash paid for fractional shares 30 Fair value of Mobile Mini Options converted to WillScot Mobile Mini Options 19,279 Total purchase price $ 1,352,836 The Merger was accounted for using the acquisition method of accounting, and WillScot is considered the accounting acquirer. Under the acquisition method of accounting, the Company is required to assign the purchase price to tangible and identifiable intangible assets acquired and liabilities assumed based on their fair values at the closing date. The excess of the purchase price over those fair values is recorded as goodwill. The Company's acquisition of Mobile Mini represents a non-cash investing outflow activity of $1,352,836 and the related issuance of equity including stock options represents a non-cash financing inflow activity of $1,352,836. The purchase price for the Merger was assigned to the underlying assets acquired and liabilities assumed based upon their fair values at the date of acquisition, July 1, 2020. The Company recorded the fair values based on independent valuations, discounted cash flow analyses, quoted market prices, contributory asset charges, and estimates made by management. The following table summarizes the July 1, 2020 preliminary fair values of the assets acquired and liabilities assumed. The final assignment of the fair value of the Merger, including the final valuation of acquired rental equipment, intangible assets, and the related deferred tax liabilities and the final assignment of goodwill to reporting units, was not complete as of December 31, 2020, but will be finalized within the allowable one-year measurement period. Opening Balance Sheet (in thousands) Current Balance Cash and cash equivalents $ 17,203 Trade receivables 87,492 (a) Inventories 8,987 Prepaid expenses and other current assets 13,264 Rental equipment 1,033,190 (b) Property, plant and equipment, net 161,401 (c) Operating lease assets 92,054 Intangible assets 382,500 (b) Goodwill identified 928,974 (d) Other non-current assets 2,387 Total identifiable assets acquired 2,727,452 Accounts payable (29,797) Accrued liabilities and interest (38,759) Deferred revenue and customer deposits (38,846) Operating lease liabilities (89,968) Debt and finance lease liabilities (897,244) Deferred tax liabilities (278,727) (e) Other long-term liabilities (1,275) Total liabilities assumed (1,374,616) Net assets acquired (purchase price) $ 1,352,836 (a) As of the acquisition date, the fair value of accounts receivable was $87.5 million, and the gross contractual amount was $99.8 million. The Company analyzed information available at the time of acquisition in estimating uncollectible receivables and the fair value of remaining receivables. The Company's analysis, as of the acquisition date, included an assessment of the risk of collectability of receivables by analyzing historical payment trends, the status of collection efforts, and any other pertinent customer specific information that existed as of the acquisition date. (b) The initial fair value assumptions used included preliminary estimates of the replacement cost of rental equipment, discount rates, royalty rates, and customer attrition rates which have been updated in preparing these valuations and the underlying assets have been adjusted from those previously recorded accordingly. Rental equipment and intangible assets were reduced by approximately $109.8 million and $183.1 million from amounts previously reported, respectively. (c) The initial fair value assumptions have been updated in preparing these valuations and the underlying assets have been adjusted from those previously recorded accordingly. Property, plant and equipment, net increased by approximately $8.2 million. (d) The goodwill is reflective of Mobile Mini’s going concern value and operational synergies that the Company expects to achieve that would not be available to other market participants. Goodwill from the Mobile Mini acquisition is not deductible for income tax purposes. (e) The deferred tax liability is reflective of a deferred tax asset valuation reversal, partially offset by a permanent difference for transaction costs. The change from the preliminary balance of deferred tax liabilities to the current balance was driven by the updates to the preliminary estimates of the replacement cost of rental equipment, discount rates, royalty rates, and customer attrition rates discussed in (b) above. Deferred tax liabilities decreased approximately $68 million from amounts previously reported. Mobile Mini has generated $316.5 million of revenue and $23.1 million of pre-tax income since the acquisition date, which is included in the consolidated statement of operations for the year ended December 31, 2020. Pro Forma Information The below pro forma results give effect to the following as if they occurred on January 1, 2019, (i) the Merger, (ii) borrowings under the Company's 2025 Secured Notes and 2020 ABL Facility (terms as defined in Note 11) used to repay certain debt in connection with the Merger, (iii) extinguishment of the Mobile Mini revolving credit facility and senior notes assumed in the Merger and immediately repaid, (iv) extinguishment of WillScot's 2017 ABL Facility and WillScot's 2022 Secured Notes (both as defined in Note 11) repaid in connection with the Merger and (v) elimination of WillScot's non-controlling interest and WillScot's Class B Common Stock in connection with the Merger. The pro forma information is not necessarily indicative of the Company’s results of operations had the Merger been completed on January 1, 2019, nor is it necessarily indicative of the Company’s future results. The pro forma information does not reflect any cost savings from operating efficiencies, synergies, or revenue opportunities that could result from the Merger. The tables below present unaudited pro forma combined statements of operations information for the years ended December 31, 2020 and 2019: (unaudited, in thousands) Year Ended December 31, 2020 Year Ended December 31, 2019 WillScot revenues $ 1,367,645 $ 1,063,665 Mobile Mini revenues 284,240 620,018 Pro forma revenues $ 1,651,885 $ 1,683,683 WillScot Mobile Mini pretax income (loss) $ 20,428 $ (13,734) (a) Mobile Mini pretax income 37,875 111,705 Pro forma pretax income 58,303 97,971 Pro forma adjustments to combined pretax income: Elimination of Merger transaction costs 80,852 — (b) Impact of fair value mark-ups on rental fleet depreciation (2,334) (4,667) (c) Other depreciation expense and intangible asset amortization (11,397) (22,399) (d) Interest expense (6,113) (1,916) (e) Elimination of Mobile Mini interest 15,921 39,672 (f) Elimination of loss on extinguishment of debt 19,682 1,512 (g) Pro forma pretax income 154,914 110,173 Income tax expense (34,549) (28,892) (h) Pro forma net income $ 120,365 $ 81,281 (a) Excludes impact of non-controlling interest which was eliminated as part of the Sapphire Exchange. See Note 12. (b) Eliminates discrete Merger transaction costs incurred as a result of the Mobile Mini Merger. (c) Depreciation on rental equipment and property, plant and equipment were adjusted for the preliminary determination of the fair value of equipment acquired in the Mobile Mini Merger. (d) Represents the differential in other depreciation and amortization expense related to the provisional fair value purchase accounting adjustments as a result of the Merger, principally the amortization of the Mobile Mini customer relationship estimated at $263 million over 13 years. (e) In connection with the Merger, the Company entered into a new ABL Facility and drew $1.47 billion at close with an estimated interest rate of 2.046%, issued the 2025 Secured Notes at 6.125%, repaid the 2022 Secured Notes and repaid the 2017 ABL Facility. Interest and amortization of deferred financing fees for the 2020 ABL Facility and the 2025 Secured Notes has been included offset by the removal of interest and amortization of deferred financing fees attributable to the 2022 Secured Notes and the 2017 ABL Facility. See Note11 for definitions of terms. (f) Interest and amortization of deferred financing fees on the senior notes and line of credit maintained by Mobile Mini which were assumed at acquisition and repaid immediately using proceeds from the 2020 ABL Facility and 2025 Secured Notes was eliminated. See Note 11 for definition of terms. (g) Elimination of loss on extinguishment of debt in connection with the redemption premium on the 2022 Secured Notes and unamortized deferred financing costs on the 2022 Secured Notes and 2017 ABL Facility. See Note11 for definitions of terms. (h) Reflects the recorded income tax provision plus the adjustment to recognize the income tax impacts of the unaudited pro forma adjustments for which a tax expense is recognized using a US federal and state statutory tax rate of 25.5%. This rate may vary from the effective tax rates of the historical and combined businesses. In addition, eliminates the 2020 reversal of $54.6 million of valuation allowance as a result of reassessment of the realizability of deferred tax assets as a result of the Merger. See Note 13. Transaction and Integration Costs The Company incurred $64.1 million in transaction costs related to the Mobile Mini Merger during the year ended December 31, 2020. Th e Company incurred $20.1 million in transaction costs during the year ended December 31, 2018 related to the ModSpace acquisition.

Revenue

Revenue	12 Months Ended
	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue	Revenue Revenue Disaggregation Geographic Areas The Company had total revenue in the following geographic areas for the years ended December 31, as follows: Year Ended December 31, (in thousands) 2020 2019 2018 US $ 1,227,465 $ 966,766 $ 685,350 Canada 79,630 80,514 50,144 Mexico 14,190 16,385 15,918 UK 46,360 — — Total revenues $ 1,367,645 $ 1,063,665 $ 751,412 Major Product and Service Lines Equipment leasing is the Company's core business, which significantly impacts the nature, timing and uncertainty of the Company's revenue and cash flows. This includes rental modular space, portable space and tank and pump units along with VAPS, which include furniture, steps, ramps, basic appliances, internet connectivity devices, and other items used by customers in connection with the Company's products. Leasing is complemented by new unit sales and sales of rental units. In connection with its leasing and sales activities, the Company provides services including delivery and installation, maintenance and ad hoc services and removal services at the end of lease transactions. The Company’s revenue by major product and service line for the years ended December 31, was as follows: Year Ended December 31, (in thousands) 2020 2019 2018 Modular space leasing revenue $ 596,880 $ 516,299 $ 360,240 Portable storage leasing revenue 125,216 24,277 21,682 Tank and pump leasing revenue 29,798 — — VAPS and third party leasing revenues (a) 202,938 159,327 104,870 Other leasing-related revenue (b) 46,615 44,282 31,443 Leasing revenue 1,001,447 744,185 518,235 Delivery and installation revenue 274,156 220,057 154,557 Total leasing and services revenue 1,275,603 964,242 672,792 New unit sales revenue 53,093 59,085 53,603 Rental unit sales revenue 38,949 40,338 25,017 Total revenues $ 1,367,645 $ 1,063,665 $ 751,412 (a) Includes $18.8 million , $15.9 million, and $10.8 million of VAPS service revenue for the years ended December 31, 2020, 2019 and 2018, respectively. (b) Includes primarily damage billings, delinquent payment charges, and other processing fees. Leasing and Services Revenue The majority of revenu e (72%, 68%, and 68% for the years ended December 31, 2020, 2019 and 2018, respectively ) is generated by lease income subject to the guidance of ASC 840, or ASC 842 for periods after January 1, 2019. The remaining revenue is generated by performance obligations in contracts with customers for services or sale of units subject to the guidance in ASC 605, or ASC 606 for periods after January 1, 2019. Future committed leasing revenues under non-cancelable operating leases with the Company’s customers at December 31, 2020 for the years ended December 31, 2021 - 2025 and thereafter were as follows: (in thousands) Operating Leases 2021 $ 232,730 2022 75,664 2023 29,419 2024 11,643 2025 4,284 Thereafter 2,738 Total $ 356,478 Receivables, Contract Assets and Liabilities The Company manages credit risk associated with its accounts receivables at the customer level. Because the same customers generate the revenues that are accounted for under both ASC 606 and ASC 842, the discussions below on credit risk and the Company's allowance for credit losses address the Company's total revenues. Concentration of credit risk with respect to the Company's receivables is limited because of a large number of geographically diverse customers who operate in a variety of end user markets. The Company's top five customers with the largest open receivables balances represent ed 4.9% and 4.1% of the total receivables balance as of December 31, 2020 and 2019, respectively. The Company manages credit risk through credit approvals, credit limits, and other monitoring procedures. The Company's allowance for credit losses reflects its estimate of the amount of receivables that it will be unable to collect . The estimated losses are based upon a review of outstanding receivables, the related aging, including specific accounts if deemed necessary, and on our historical collection experience. The estimated losses are calculated using the loss rate method based upon a review of outstanding receivables, related aging, and historical collection experience. T he Company's estimates reflect changing circumstances, including changes in the economy or in the particular circumstances of individual customers, and as a result, the Company may be required to increase or decrease its allowance. During the years ended December 31, 2020, 2019, and 2018, the Company recognized bad debt expense of $13.4 million, $4.5 million , and $7.7 million, respectively, within SG&A expense in its consolidated statements of operations, which included changes in its allowances for credit losses . In accordance with the collectability provisions of ASC 842, the Company has recorded $18.0 million and $10.0 million as reductions of revenue in 2020 and 2019, respectively, that would have been recorded as bad debt expense prior to the adoption of ASC 842. When customers are billed in advance, the Company defers recognition of revenue until the related services are performed, which generally occurs at the end of the contract. During the years ended December 31, 2020 and 2019, $37.5 million and $14.0 million, respectively, of deferred revenue relating to these services, was recognized as revenue. At December 31, 2020 and 2019, the Company had approximately $74.1 million and $42.6 million, respectively, of deferred revenue related to these services. The Company does not have material contract assets, and it did not recognize any material impairments of any contract assets. The Company's uncompleted contracts with customers have unsatisfied (or partially satisfied) performance obligations. For the future services revenues that are expected to be recognized within twelve months, the Company has elected to utilize the optional disclosure exemption made available regarding transaction price allocated to unsatisfied (or partially unsatisfied) performance obligations. The transaction price for performance obligations that will be completed in greater than twelve months is variable based on the costs ultimately incurred to provide those services and therefore the Company is applying the optional exemption to omit disclosure of such amounts. The primary costs to obtain contracts for new and rental unit sales with the Company's customers are commissions. The Company pays its sales force commissions on the sale of new and rental units. For new and rental unit sales, the period benefited by each commission is less than one year. As a result, the Company has applied the practical expedient for incremental costs of obtaining a sales contract and expenses commissions as incurred. Deferred revenue and customer deposits at December 31 consist ed of the following: (in thousands) 2020 2019 Current: Deferred revenue $ 133,156 $ 81,303 Customer deposits 2,329 1,675 Total current deferred revenue and customer deposits $ 135,485 $ 82,978 Long-term: Deferred revenue $ 12,060 $ 12,342 Total long-term deferred revenue and customer deposits $ 12,060 $ 12,342 Total long-term deferred revenue and customer deposits are included in Other non-current liabilities on the consolidated balance sheets.

Leases

Leases	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Lessee, Operating Leases	Leases As of December 31, 2020, the undiscounted future lease payments for operating and finance lease liabilities were as follows (in thousands): Operating Finance 2021 $ 60,120 $ 18,252 2022 51,184 17,158 2023 41,074 13,707 2024 33,336 10,786 2025 26,542 10,893 Thereafter 67,421 13,410 Total lease payments 279,677 84,206 Less: interest (47,853) (6,332) Present value of lease liabilities $ 231,824 $ 77,874 As of December 31, 2019, the undiscounted future lease payments for operating and finance lease liabilities were as follows (in thousands): Operating Finance 2020 $ 37,648 $ — 2021 33,903 — 2022 27,769 — 2023 21,926 — 2024 16,685 — Thereafter 47,916 — Total lease payments 185,847 — Less: interest (38,285) — Present value of lease liabilities $ 147,562 $ — Finance lease liabilities are included within long-term debt and current portion of long-term debt on the consolidated balance sheets. The Company’s lease activity during the years ended December 31, 2020 and 2019 was as follows: Year Ended December 31, Financial Statement Line (in thousands) 2020 2019 Finance Lease Expense Amortization of finance lease assets $ 9,556 $ — Interest on obligations under finance leases 1,081 — Total finance lease expense $ 10,637 $ — Operating Lease Expense Fixed lease expense Cost of leasing and services $ 5,723 $ 6,737 Selling, general and administrative 43,482 34,058 Lease impairment expense and other related charges 2,800 2,611 Short-term lease expense Cost of leasing and services 25,576 29,729 Selling, general and administrative 2,067 2,071 Lease impairment expense and other related charges 471 — Variable lease expense Cost of leasing and services 6,981 3,787 Selling, general and administrative 5,436 4,231 Lease impairment expense and other related charges 855 — Total operating lease expense $ 93,391 $ 83,224 The Company initiated certain restructuring plans associated with the 2018 ModSpace acquisition in order to capture operating synergies as a result of integrating ModSpace into WillScot. The restructuring activities primarily included the termination of leases for duplicative branches, equipment, and corporate facilities. As part of these plans, certain of its leased locations were vacated and leases were terminated or impaired. During the year ended December 31, 2020, the Company recorded $4.9 million in lease impairment expense and other related charges which is comprised of $0.7 million loss on lease exit and impairment charges and $4.2 million in closed location rent expense. During the year ended December 31, 2019, the Company recorded $8.7 million in lease impairment expense and other relat ed charges which is comprised of $4.2 million in ROU asset impairment on leased locations no longer used in operations, $1.9 million loss on lease exit and $2.6 million in closed location rent expense. Rent expense included in the consolidated statement of operations was $31.0 million for the year ended December 31, 2018. Supplemental cash flow information related to leases for the years ended December 31, 2020 and 2019 were as follows: Year Ended December 31, Supplemental Cash Flow Information (in thousands) 2020 2019 Cash paid for the amounts included in the measurement of lease liabilities: Operating cash outflows from operating leases $ 45,883 $ 42,111 Financing cash outflows from finance leases $ 9,568 $ — Right of use assets obtained in exchange for lease obligations $ 33,576 $ 43,013 Assets obtained in exchange for finance leases $ 9,089 $ — Weighted-average remaining operating lease terms and the weighted average discount rates as of December 31, 2020 and 2019 were as follows: Lease Terms and Discount Rates December 31, 2020 December 31, 2019 Weighted-average remaining lease term - operating leases 6.4 years 6.5 years Weighted-average discount rate - operating leases 5.7 % 7.0 % Weighted-average remaining lease term - finance leases 4.6 years — Weighted-average discount rate - finance leases 2.9 % — The Company presents information related to leasing revenues in Note 3.

Inventories

Inventories	12 Months Ended
	Dec. 31, 2020
Inventory Disclosure [Abstract]
Inventories	Inventories Inv entories at December 31, consisted of the following: (in thousands) 2020 2019 Raw materials $ 19,560 $ 15,387 Finished units 2,095 — Inventories $ 21,655 $ 15,387

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	12 Months Ended
	Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid Expenses and Other Current Assets	Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets at December 31 co nsisted of the following: (in thousands) 2020 2019 Tax receivables $ 4,618 $ 1,211 Prepaid insurance 5,859 2,099 Other prepaid expenses 19,477 11,311 Total prepaid expenses and other current assets $ 29,954 $ 14,621

Rental Equipment, Net

Rental Equipment, Net	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Rental Equipment, Net	Rental Equipment, net Rental equipment, net at December 31 consisted of the following: (in thousands) 2020 2019 Modular space units $ 2,520,704 $ 2,372,069 Portable storage units 931,363 83,402 Tank and pump products 132,071 — Value added products 143,652 121,855 Total rental equipment 3,727,790 2,577,326 Less: accumulated depreciation (794,068) (632,890) Rental equipment, net $ 2,933,722 $ 1,944,436 Property, plant and equipment, net at December 31 consisted of the following: (in thousands) 2020 2019 Land, buildings, and leasehold improvements $ 154,210 $ 139,861 Vehicles, machinery, and office equipment 227,009 62,169 Software and other 20,800 27,342 Total property, plant and equipment 402,019 229,372 Less: accumulated depreciation (98,369) (81,683) Property, plant and equipment, net $ 303,650 $ 147,689 Depreciation expense related to property, plant and equipment was $28.9 million , $11.4 million, and $12.2 million for the years ended December 31, 2020, 2019 and 2018, respectively.

Property, Plant and Equipment,

Property, Plant and Equipment, net	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, net	Rental Equipment, net Rental equipment, net at December 31 consisted of the following: (in thousands) 2020 2019 Modular space units $ 2,520,704 $ 2,372,069 Portable storage units 931,363 83,402 Tank and pump products 132,071 — Value added products 143,652 121,855 Total rental equipment 3,727,790 2,577,326 Less: accumulated depreciation (794,068) (632,890) Rental equipment, net $ 2,933,722 $ 1,944,436 Property, plant and equipment, net at December 31 consisted of the following: (in thousands) 2020 2019 Land, buildings, and leasehold improvements $ 154,210 $ 139,861 Vehicles, machinery, and office equipment 227,009 62,169 Software and other 20,800 27,342 Total property, plant and equipment 402,019 229,372 Less: accumulated depreciation (98,369) (81,683) Property, plant and equipment, net $ 303,650 $ 147,689 Depreciation expense related to property, plant and equipment was $28.9 million , $11.4 million, and $12.2 million for the years ended December 31, 2020, 2019 and 2018, respectively.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill Changes in the carrying amount of goodwill were as follows: (in thousands) Balance at December 31, 2018 $ 247,017 Changes to purchase price accounting - Modspace (13,479) Effects of movements in foreign exchange rates 1,639 Balance at December 31, 2019 235,177 Acquisition of Mobile Mini 928,974 Effects of movements in foreign exchange rates 7,068 Balance at December 31, 2020 $ 1,171,219 As discussed further in Note 2, the Company acquired Mobile Mini on July 1, 2020. Goodwill was preliminarily allocated to the NA Storage, UK Storage and Tank and Pump segments, as defined in Note 17, in the amounts of $726.5 million, $59.2 million and $143.3 million, respectively. The Company expects to finalize the valuation of the acquired net assets of Mobile Mini, including the final assignment of goodwill to reporting units, within the one-year measurement period from the date of acquisition. The Company expects any adjustments to goodwill for financial reporting to be non-deductible for income tax purposes. The Company conducted its annual impairment test of goodwill as of October 1, 2020 and determined that there was no impairment of goodwill identified as a result of the annual impairment analysis. The Company considered the economic environment resulting from the COVID-19 pandemic as part of its goodwill impairment test. Due to the uncertain and rapidly evolving nature of the conditions surrounding the COVID-19 pandemic, changes in economic outlook may change the Company's long-term projections. Accumulated goodwill impairment losses wer e $792.8 million and pertain to the NA Modular segment. There were no goodwill impairments recorded for the years ended December 31, 2020, 2019 and 2018. Intangibles Intangible assets other than goodwill at December 31, consisted of the following: December 31, 2020 (in thousands) Weighted average remaining life (in years) Gross carrying amount Accumulated amortization Net book value Intangible assets subject to amortization: Trade name - ModSpace 0.7 $ 3,000 $ (2,375) $ 625 Mobile Mini customer relationships 8.0 217,000 (12,053) 204,947 Technology 5.5 1,500 (125) 1,375 Indefinite-lived intangible assets: Trade name - Mobile Mini 164,000 — 164,000 Trade name - WillScot 125,000 — 125,000 Total intangible assets other than goodwill $ 510,500 $ (14,553) $ 495,947 December 31, 2019 (in thousands) Weighted average remaining life (in years) Gross carrying amount Accumulated amortization Net book value Intangible assets subject to amortization: Trade name - ModSpace 1.7 $ 3,000 $ (1,375) $ 1,625 Total intangible assets subject to amortization 3,000 (1,375) 1,625 Indefinite-lived intangible assets: Trade name - WillScot 125,000 — 125,000 Total intangible assets other than goodwill $ 128,000 $ (1,375) $ 126,625 As discussed further in Note 2, the Company acquired Mobile Mini on July 1, 2020. The Company preliminarily recorded $164.0 million of indefinite-lived intangible assets and $218.5 million of intangibles subject to amortization, related to Mobile Mini customer relationships and technology, respectively, in the NA Storage, UK Storage, and Tank and Pump segments. The Company expects to finalize the valuation of the acquired net assets of Mobile Mini, including the related intangible assets, within the one-year measurement period from the date of acquisition. The Company expects any adjustments to intangible assets for financial reporting to be non-deductible for income tax purposes. In the 2018 ModSpace acquisition, the Company allocated $3.0 million to definite-lived intangible assets, related to the ModSpace trade name. At the time of the acquisition, management estimated that the ModSpace trade name had an estimated useful life of three years. For the years ended December 31, 2020 and 2019, the aggregate amount recorded to depreciation and amortization expense for intangible assets subject to amortization, was $14.4 million and $1.0 million, respectively. As of December 31, 2020, the expected future amortization expense for intangible assets is as follows: (in thousands) Amortization Expense 2021 $ 27,167 2022 26,542 2023 26,542 2024 26,542 2025 26,542 Thereafter 73,612 Total $ 206,947

Deferred Revenue and Customer D

Deferred Revenue and Customer Deposits	12 Months Ended
	Dec. 31, 2020
Other Liabilities Disclosure [Abstract]
Deferred Revenue and Customer Deposits	Revenue Revenue Disaggregation Geographic Areas The Company had total revenue in the following geographic areas for the years ended December 31, as follows: Year Ended December 31, (in thousands) 2020 2019 2018 US $ 1,227,465 $ 966,766 $ 685,350 Canada 79,630 80,514 50,144 Mexico 14,190 16,385 15,918 UK 46,360 — — Total revenues $ 1,367,645 $ 1,063,665 $ 751,412 Major Product and Service Lines Equipment leasing is the Company's core business, which significantly impacts the nature, timing and uncertainty of the Company's revenue and cash flows. This includes rental modular space, portable space and tank and pump units along with VAPS, which include furniture, steps, ramps, basic appliances, internet connectivity devices, and other items used by customers in connection with the Company's products. Leasing is complemented by new unit sales and sales of rental units. In connection with its leasing and sales activities, the Company provides services including delivery and installation, maintenance and ad hoc services and removal services at the end of lease transactions. The Company’s revenue by major product and service line for the years ended December 31, was as follows: Year Ended December 31, (in thousands) 2020 2019 2018 Modular space leasing revenue $ 596,880 $ 516,299 $ 360,240 Portable storage leasing revenue 125,216 24,277 21,682 Tank and pump leasing revenue 29,798 — — VAPS and third party leasing revenues (a) 202,938 159,327 104,870 Other leasing-related revenue (b) 46,615 44,282 31,443 Leasing revenue 1,001,447 744,185 518,235 Delivery and installation revenue 274,156 220,057 154,557 Total leasing and services revenue 1,275,603 964,242 672,792 New unit sales revenue 53,093 59,085 53,603 Rental unit sales revenue 38,949 40,338 25,017 Total revenues $ 1,367,645 $ 1,063,665 $ 751,412 (a) Includes $18.8 million , $15.9 million, and $10.8 million of VAPS service revenue for the years ended December 31, 2020, 2019 and 2018, respectively. (b) Includes primarily damage billings, delinquent payment charges, and other processing fees. Leasing and Services Revenue The majority of revenu e (72%, 68%, and 68% for the years ended December 31, 2020, 2019 and 2018, respectively ) is generated by lease income subject to the guidance of ASC 840, or ASC 842 for periods after January 1, 2019. The remaining revenue is generated by performance obligations in contracts with customers for services or sale of units subject to the guidance in ASC 605, or ASC 606 for periods after January 1, 2019. Future committed leasing revenues under non-cancelable operating leases with the Company’s customers at December 31, 2020 for the years ended December 31, 2021 - 2025 and thereafter were as follows: (in thousands) Operating Leases 2021 $ 232,730 2022 75,664 2023 29,419 2024 11,643 2025 4,284 Thereafter 2,738 Total $ 356,478 Receivables, Contract Assets and Liabilities The Company manages credit risk associated with its accounts receivables at the customer level. Because the same customers generate the revenues that are accounted for under both ASC 606 and ASC 842, the discussions below on credit risk and the Company's allowance for credit losses address the Company's total revenues. Concentration of credit risk with respect to the Company's receivables is limited because of a large number of geographically diverse customers who operate in a variety of end user markets. The Company's top five customers with the largest open receivables balances represent ed 4.9% and 4.1% of the total receivables balance as of December 31, 2020 and 2019, respectively. The Company manages credit risk through credit approvals, credit limits, and other monitoring procedures. The Company's allowance for credit losses reflects its estimate of the amount of receivables that it will be unable to collect . The estimated losses are based upon a review of outstanding receivables, the related aging, including specific accounts if deemed necessary, and on our historical collection experience. The estimated losses are calculated using the loss rate method based upon a review of outstanding receivables, related aging, and historical collection experience. T he Company's estimates reflect changing circumstances, including changes in the economy or in the particular circumstances of individual customers, and as a result, the Company may be required to increase or decrease its allowance. During the years ended December 31, 2020, 2019, and 2018, the Company recognized bad debt expense of $13.4 million, $4.5 million , and $7.7 million, respectively, within SG&A expense in its consolidated statements of operations, which included changes in its allowances for credit losses . In accordance with the collectability provisions of ASC 842, the Company has recorded $18.0 million and $10.0 million as reductions of revenue in 2020 and 2019, respectively, that would have been recorded as bad debt expense prior to the adoption of ASC 842. When customers are billed in advance, the Company defers recognition of revenue until the related services are performed, which generally occurs at the end of the contract. During the years ended December 31, 2020 and 2019, $37.5 million and $14.0 million, respectively, of deferred revenue relating to these services, was recognized as revenue. At December 31, 2020 and 2019, the Company had approximately $74.1 million and $42.6 million, respectively, of deferred revenue related to these services. The Company does not have material contract assets, and it did not recognize any material impairments of any contract assets. The Company's uncompleted contracts with customers have unsatisfied (or partially satisfied) performance obligations. For the future services revenues that are expected to be recognized within twelve months, the Company has elected to utilize the optional disclosure exemption made available regarding transaction price allocated to unsatisfied (or partially unsatisfied) performance obligations. The transaction price for performance obligations that will be completed in greater than twelve months is variable based on the costs ultimately incurred to provide those services and therefore the Company is applying the optional exemption to omit disclosure of such amounts. The primary costs to obtain contracts for new and rental unit sales with the Company's customers are commissions. The Company pays its sales force commissions on the sale of new and rental units. For new and rental unit sales, the period benefited by each commission is less than one year. As a result, the Company has applied the practical expedient for incremental costs of obtaining a sales contract and expenses commissions as incurred. Deferred revenue and customer deposits at December 31 consist ed of the following: (in thousands) 2020 2019 Current: Deferred revenue $ 133,156 $ 81,303 Customer deposits 2,329 1,675 Total current deferred revenue and customer deposits $ 135,485 $ 82,978 Long-term: Deferred revenue $ 12,060 $ 12,342 Total long-term deferred revenue and customer deposits $ 12,060 $ 12,342 Total long-term deferred revenue and customer deposits are included in Other non-current liabilities on the consolidated balance sheets.

Debt

Debt	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Debt	Debt The carrying value of debt outstanding at December 31 consisted of the following: (in thousands, except rates) Interest rate Year of maturity 2020 2019 2022 Secured Notes 7.875% 2022 $ — $ 264,576 2023 Secured Notes 6.875% 2023 — 482,768 2025 Secured Notes 6.125% 2025 637,068 — ABL Facility (a) Varies 2025 1,263,833 885,245 2028 Secured Notes 4.625% 2028 491,555 — Finance Leases Varies Varies 77,874 — Total debt 2,470,330 1,632,589 Less: current portion of long-term debt 16,521 — Total long-term debt $ 2,453,809 $ 1,632,589 (a) As of December 31, 2020, the Company had no outstanding principal borrowings on the Multicurrency Facility and $7.9 million of related debt issuance costs. No related debt issuance costs were recor ded as a direct offset against the principal borrowings on the Multicurrency Facility, and the $7.9 million in excess of principal was included in other non-current assets on the consolidated balance sheet. As of December 31, 2019, the Company had no outstanding principal borrowings on the 2017 Canadian ABL Facility and $2.1 million of related debt issuance costs. No related debt issuance costs were recorded as a direct offset against the principal of the 2017 Canadian ABL Facility, and the $2.1 million in excess of principal was included in other non-current assets on the consolidated balance sheet. Maturities of long-term debt, including finance leases, during the years subsequent to December 31, 2020 are as follows: (in thousands) 2021 $ 18,252 2022 $ 17,158 2023 $ 13,707 2024 $ 10,786 2025 $ 1,965,505 Thereafter $ 513,410 The Company has de bt issuance costs recorded as offsets against the carrying value of the related debt . These debt costs will be amortized and included as part of interest expense over the remaining contractual terms of those debt instruments for each of the next five years as follows: (in thousands) Debt issuance cost amortization 2021 $ 14,317 2022 $ 14,540 2023 $ 14,778 2024 $ 15,031 2025 $ 8,050 Thereafter $ 3,365 Asset Backed Lending Facilities 2017 ABL Facility On November 29, 2017, Williams Scotsman Holdings Corp ("Holdings"), Williams Scotsman International, Inc. ("WSII"), and certain of its subsidiaries entered into an ABL credit agreement (the "2017 ABL Facility"), as amended, that provided a senior secured revolving credit facility that matured on May 29, 2022. The 2017 ABL Facility consisted of (i) a $1.285 billion asset-backed revolving credit facility for WSII and certain of its domestic subsidiaries (the "2017 US ABL Facility"), (ii) a $140.0 million asset-based revolving credit facility (the “2017 Canadian ABL Facility”) for certain Canadian subsidiaries of WSII , and (iii) an accordion feature that permitted the borrowers to increase the lenders’ commitments in an aggregate amount not to exceed $375.0 million, subject to the satisfaction of customary conditions and lender approval, plus any voluntary prepayments that are accompanied by permanent commitment reductions under the 2017 ABL Facility. Borrowing availability under the 2017 ABL Facility was equal to the lesser of $1.425 billion and the applicable borrowing bases. The borrowing bases were a function of, among other things, the value of the assets in the collateral pool. Borrowings under the 2017 ABL Facility bore interest at an adjusted LIBOR or base rate, in each case plus an applicable margin. The initial applicable margin was 2.50% for LIBOR borrowings and 1.50% for base rate borrowings. Commencing on March 31, 2018, the applicable margins were subject to one step down of 0.25% or one step-up of 0.25%, based on excess availability levels with respect to the 2017 ABL Facility. The 2017 ABL Facility required the payment of an annual commitment fee on the unused available borrowings between 0.375% and 0.5% per annum. At December 31, 2019, the weighted average interest rate for borrowings under the 2017 ABL Facility was 4.51%. The weighted average interest rate on the balance outstanding as of December 31, 2019, as adjusted for the effects of the interest rate swaps was 5.10%. Refer to Note 14 for a more detailed discussion on interest rate management. At December 31, 2019, under the 2017 ABL Facility, the aggregate Borrowing Base ("Line Cap") was $1.425 billion and the Borrowers had $509.1 million of available borrowing capacity, including $369.3 million under the 2017 US ABL Facility and $139.8 million under the 2017 Canadian ABL Facility. Borrowing capacity under the 2017 US ABL Facility was made available for up to $75 million of letters of credit and up to $75 million of swingline loans, and borrowing capacity under the 2017 Canadian ABL Facility was made available for up to $60.0 million of letters of credit and $50 million of swingline loans. At December 31, 2019, letters of credit and bank guarantees carried fees of 2.875%. The Company had issued $12.7 million of standby letters of credit under the 2017 ABL Facility at December 31, 2019. The Company had $903.0 million in outstanding principal under the 2017 ABL Facility at December 31, 2019. Debt issuance costs of $17.8 million were included in the carrying value of the 2017 ABL Facility at December 31, 2019. 2020 ABL Facility On July 1, 2020, in connection with the completion of the Merger, Holdings, WSII, and certain of its subsidiaries, entered into a new asset-based credit agreement that provides for revolving credit facilities in the aggregate principal amount of up to $2.4 billion, consisting of: (i) a senior secured asset-based US dollar revolving credit facility in the aggregate principal amount of $2.0 billion (the "US Facility"), available to WSII and certain of its subsidiaries (collectively, the "US Borrowers"), and (ii) a $400.0 million senior secured asset-based multicurrency revolving credit facility (the "Multicurrency Facility," together with the US Facility, the "2020 ABL Facility"), available to be drawn in US Dollars, Canadian Dollars, British Pounds Sterling or Euros by the US Borrowers, and certain of WSII's wholly-owned subsidiaries organized in Canada and in the UK. On July 1, 2020, in connection with the completion of the Merger, approximately $1.47 billion of proceeds from the 2020 ABL Facility were used to repay the 2017 ABL Facility and the asset-backed lending facility assumed in the transaction with Mobile Mini, as well as, to pay fees and expense related to the Merger and the related financing transactions. In connection with the repayment of the 2017 ABL facility, the Company wrote off $4.4 million of deferred financing costs to loss on extinguishment of debt. The 2020 ABL Facility matures on July 1, 2025. Borrowings under the 2020 ABL Facility initially bear interest at (i) in the case of US Dollars, at WSII's option, either an adjusted LIBOR rate plus 1.875% or an alternative base rate plus 0.875%, (ii) in the case of Canadian Dollars, at WSII's option, either a Canadian BA rate plus 1.875% or Canadian prime rate plus 0.875%, and (iii) in the case of Euros and British Pounds Sterling, an adjusted LIBOR rate plus 1.875%. The 2020 ABL Facility requires the payment of an annual commitment fee on the unused available borrowings of 0.225% per annum . At December 31, 2020, t he weighted average interest rate for borrowings under the 2020 ABL Faci lity was 2.05% . T he weighted average interest rate on the balance outstanding as of year end, as adjusted for the effects of the interest rate swap agreements was 2.94% . Refer to Note 14 for a more detailed discussion on interest rate management. Borrowing availability under the US Facility and the Multicurrency Facility is equal to the lesser of (i) the aggregate Revolver Commitments and (ii) the Line Cap. At December 31, 2020, the Line Cap was $2.4 billion and the Borrowers had $1.1 billion of available borrowing capacity under the 2020 ABL Facility, including $681.0 million under the US ABL Facility and $400.0 million un der the Multicurrency Facility. Borrowing capacity under the 2020 ABL Facility is made available for up to $205.6 million of letters of credit and up to $170.0 million of swingline loans. At December 31, 2020, letters of credit and bank guarantees carried fees of 2.00% . The Company had issued $14.4 million of standby letters of credit under the 2020 ABL Facility at December 31, 2020. The Company had $1.3 billion outstanding principal under the 2020 ABL Facility at December 31, 2020. Debt issuance costs of $40.8 million were included in the carrying value of the 2020 ABL Facility at December 31, 2020. The obligations of the US Borrowers are unconditionally guaranteed by Holdings and each existing and subsequently acquired or organized direct or indirect wholly-owned US organized restricted subsidiary of Holdings, other than excluded subsidiaries (together with Holdings, the "US Guarantors"). The obligations of the Multicurrency Borrowers are unconditionally guaranteed by the US Borrowers and the US Guarantors, and each existing and subsequently acquired or organized direct or indirect wholly-owned Canadian organized restricted subsidiary of Holdings other than certain excluded subsidiaries (together with the US Guarantors, the "ABL Guarantors"). 2022 Senior Secured Notes In 2017, WSII issued $300.0 million aggregate principal amount of 7.875% senior secured notes due December 15, 2022 (the “2022 Secured Notes”) under an indenture dated November 29, 2017. Interest was payable semi-annually on June 15 and December 15 beginning June 15, 2018. On December 13, 2019, the Company completed a partial redemption of $30.0 million of the 2022 Secured Notes at a redemption price of 103% using proceeds from its 2017 ABL Facility. The Company recorded a loss on extinguishment of debt of $1.5 million, which included $0.9 million of an early redemption premium and $0.6 million related to the write-off of unamortized deferred financing fees. In connection with the Merger and related financing transactions in the third quarter of 2020, using proceeds from the 2025 Secured Notes discussed below, the Company redeemed all of its 2022 Secured Notes and recorded a loss on extinguishment of debt in the consolidated statements of operations of $15.2 million comprised of a redemption premium of $10.6 million and write off of unamortized deferred financing fees of $4.6 million. As of December 31, 2019, unamortized debt issuance costs pertaining to the 2022 Secured Notes were $5.4 million. 2023 Senior Secured Notes In connection with the acquisition of ModSpace in 2018, $300.0 million in aggregate principal amount of its 6.875% senior secured notes due August 15, 2023 (the “2023 Secured Notes”) were issued. Interest was payable semi-annually on February 15 and August 15 of each year, beginning February 15, 2019. On May 14, 2019, WSII completed a tack-on offering of $190.0 million in aggregate principal amount to the initial 2023 Secured Notes (the "Tack-On Notes"). The Tack-On Notes were issued as additional securities under the 2023 Secured Notes indenture. The Tack-On Notes and the initial 2023 Secured Notes were treated as a single class of debt securities under the 2023 Secured Notes indenture. The Tack-On Notes have identical terms to the initial 2023 Secured Notes, other than with respect to the issue date and issue price. WSII incurred a total of $3.0 million in debt issuance costs in connection with the tack-on offering, which were deferred and were being amortized through the August 15, 2023 maturity date. Subsequent to the Tack-On Notes, WSII had $490.0 million of 6.875% 2023 Secured Notes. On August 11, 2020, WSII redeemed 10% of the outstanding principal amount of the 2023 Secured Notes, $49.0 million, at a redemption price of 103% plus accrued interest and unpaid interest. This repayment was funded by borrowings under the Company's 2020 ABL Facility. On August 25, 2020, the Company completed a private offering of its 2028 Secured Notes, discussed below, and used the offering proceeds to repay, along with expenses, the $441.0 million outstanding principal amount of its 2023 Secured Notes at a redemption price of 103.438% plus accrued interest and unpaid interest. The Company recorded a loss on extinguishment of debt in the consolidated statements of operations of $22.7 million comprised of a redemption premium of $16.6 million and a write off of unamortized deferred financing fees of $6.1 million. Unamortized debt issuance costs of $7.2 million were included in the carrying value of the debt as of December 31, 2019. 2025 Senior Secured Notes In anticipation of the Merger, on June 15, 2020, Picasso Finance Sub, Inc., a newly-formed indirect finance subsidiary (the "Finance Sub") of the Company completed a private offering of $650.0 million in aggregate principal amount of its 6.125% senior secured notes due 2025 (the "2025 Secured Notes"). The 2025 Secured Notes contained provisions requiring repayment, without penalty, in the event the Merger was not consummated. The offering proceeds from the 2025 Secured Notes of $650.0 million and $5.1 million of interest due through August 1, 2020 were deposited into an escrow account, pending the closing of the Merger. In connection with the completion of the Merger, on July 1, 2020, the offering proceeds were released and the proceeds were used to repay the 2022 Secured Notes, repay Mobile Mini senior notes assumed in the acquisition and pay certain fees and expenses related to the Merger and the related financing transactions. In addition, Finance Sub was merged into WSII on July 1, 2020. The Company recorded $14.3 million in deferred financing fees related to the 2025 Secured Notes. The 2025 Secured Notes mature on June 15, 2025 and bear interest at a rate of 6.125% per annum. Interest is payable semi-annually on June 15 and December 15 of each year, beginning December 15, 2020. The Company may redeem the 2025 Secured Notes at any time before June 15, 2022 at a redemption price equal to 100% of the principal amount thereof, plus a customary make whole premium for the 2025 Secured Notes being redeemed, plus accrued and unpaid interest, if any, to but not including the redemption date. Before June 15, 2022, the Company may redeem up to 40% of the aggregate principal amount of the 2025 Secured Notes at a price equal to 106.125% of the principal amount of the 2025 Secured Notes being redeemed, plus accrued and unpaid interest, if any, to but not including the redemption date with the net proceeds of certain equity offerings. At any time prior to June 15, 2022, the Company may also redeem up to 10% of the aggregate principal amount of the 2025 Secured Notes at a redemption price equal to 103% of the principal amount of the 2025 Secured Notes being redeemed during each twelve-month period commencing with the issue date, plus accrued and unpaid interest, if any, to but not including the redemption date. If the Company undergoes a change of control or sells certain of its assets, the Company may be required to offer to repurchase the 2025 Secured Notes. On and after June 15, 2022, the Company may redeem the 2025 Secured Notes, in whole or in part, at the redemption prices expressed as percentages of principal amount set forth below plus accrued and unpaid interest to but not including the applicable redemption date, subject to the holders' right to receive interest due on an interest payment date falling on or prior to the redemption date, if redeemed during the twelve-month period beginning on June 15 of each of the years set forth below. Year Redemption Price 2022 103.063 % 2023 101.531 % 2024 and thereafter 100.000 % The 2025 Secured Notes are unconditionally guaranteed by each of WSII's direct and indirect domestic subsidiaries and WSII's parent, Holdings (collectively, "the Note Guarantors"). WillScot Mobile Mini is not a guarantor of the 2025 Secured Notes. The Note Guarantors, as well as certain of the Company’s non-US subsidiaries, are guarantors or borrowers under the 2020 ABL Facility. To the extent lenders under the 2020 ABL Facility release the guarantee of any Note Guarantor, such Note Guarantor will also be released from obligations under the 2025 Secured Notes. These guarantees are secured by a second priority security interest in substantially all of the assets of WSII and the Note Guarantors, subject to customary exclusions. The guarantees of the 2025 Secured Notes by WillScot Equipment II, LLC, a Delaware limited liability company which holds certain of WSII’s assets in the US, will be subordinated to its obligations under the 2020 ABL Facility. Unamortized deferred financing costs pertaining to the 2025 Secured Notes were $12.9 million as of December 31, 2020. 2028 Senior Secured Notes On August 25, 2020, the Company completed a private offering of $500.0 million in aggregate principal amount of 4.625% senior secured notes due 2028 (the "2028 Secured Notes"). The 2028 Secured Notes mature on August 15, 2028. They bear interest at a rate of 4.625% per annum. Interest is payable semi-annually on August 15 and February 15 of each year, beginning February 15, 2021. The Company may redeem the 2028 Secured Notes at any time before August 15, 2023 at a redemption price equal to 100% of the principal amount thereof, plus a customary make whole premium for the 2028 Secured Notes being redeemed, plus accrued and unpaid interest, if any, to but not including the redemption date. Before August 15, 2023, the Company may redeem up to 40% of the aggregate principal amount of the 2028 Secured Notes at a price equal to 104.625% of the principal amount of the 2028 Secured Notes being redeemed, plus accrued and unpaid interest, if any, to but not including the redemption date with the net proceeds of certain equity offerings. At any time prior to August 15, 2023, the Company may also redeem up to 10% of the aggregate principal amount at a redemption price equal to 103% of the principal amount of the 2028 Secured Notes being redeemed during each twelve-month period commencing with the issue date, plus accrued and unpaid interest, if any, to but not including the redemption date. If the Company undergoes a change of control or sells certain of its assets, the Company may be required to offer to repurchase the 2028 Secured Notes. On and after August 15, 2023, the Company may redeem the 2028 Secured Notes, in whole or in part, at the redemption prices expressed as percentages of principal amount set forth below plus accrued and unpaid interest to but not including the applicable redemption date, subject to the holders' right to receive interest due on an interest payment date falling on or prior to the redemption date, if redeemed during the twelve-month period beginning on August 15 of each of the years set forth below. Year Redemption Price 2023 102.313 % 2024 101.156 % 2025 and thereafter 100.000 % The 2028 Secured Notes are unconditionally guaranteed by the Note Guarantors. WillScot Mobile Mini is not a guarantor of the 2028 Secured Notes. The Note Guarantors, as well as certain of the Company’s non-US subsidiaries, are guarantors or borrowers under the 2020 ABL Facility. To the extent lenders under the 2020 ABL Facility release the guarantee of any Note Guarantor, such Note Guarantor will also be released from obligations under the 2025 Secured Notes. These guarantees are secured by a second priority security interest in substantially all of the assets of WSII and the Note Guarantors, subject to customary exclusions. The guarantees of the 2028 Secured Notes by WillScot Equipment II, LLC, a Delaware limited liability company which holds certain of WSII’s assets in the US, will be subordinated to its obligations under the 2020 ABL Facility. Unamortized deferred financing costs pertaining to the 2028 Secured Notes were $8.4 million as of December 31, 2020. The Company is in compliance with all debt covenants and restrictions for the aforementioned debt instruments as of December 31, 2020. 2023 Senior Unsecured Notes The Company had $200.0 million in aggregate principal amount of senior unsecured notes due November 15, 2023. On June 19, 2019 (the "Redemption Date"), WSII used proceeds from its US ABL Facility to redeem all $200.0 million in aggregate outstanding principal amount of the unsecured notes at a redemption price of 102.0%, plus a make-whole premium of 1.126% and any accrued and unpaid interest to, but not including, the Redemption Date. The Company recorded a loss on extinguishment of $7.2 million, which included $6.2 million of make-whole premiums and $1.0 million related to the write-off of unamortized deferred financing fees. Finance Leases The Company maintains finance leases primarily related to transportation equipment. At December 31, 2020, obligations under the finance leases for certain real property and transportation related equi pment were $77.9 million. The C ompany had no finance leases at December 31, 2019. Mobile Mini Debt Mobile Mini had $250.0 million in aggregate principal amount of 5.875% senior notes outstanding prior to the Merger. Interest was payable semi-annually on January 1 and July 1. In connection with the Merger, these notes were assumed by WillScot Mobile Mini and subsequently redeemed using proceeds from the 2025 Secured Notes discussed above. Mobile Mini had a $1.0 billion first lien senior secured revolving credit facility. At June 30, 2020, Mobile Mini had $563.2 million of outstanding principal on the credit facility. In connection with the Merger, this line of credit was assumed by WillScot Mobile Mini and subsequently repaid in full using proceeds from the 2020 ABL Facility discussed above.

Equity

Equity	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Equity	Equity Preferred Stock WillScot Mobile Mini's certificate of incorporation authorizes the issuance of 1,000,000 shares of Preferred Stock with a par value of $0.0001 per share. As of December 31, 2020 , the Company has zero shares of Preferred Stock issued and outstanding. Common Stock WillScot Mobile Mini's certificate of incorporation authorizes the issuance of 500,000,000 shares of Common Stock with a par value of $0.0001 per share. The Company has 229,038,158 shares of Common Stock issued and outstanding as of December 31, 2020 . The outstanding shares of the Company's Common Stock are duly authorized, validly issued, fully paid and non-assessable. On July 30, 2018, WillScot closed a public offering of 8,000,000 shares of its Class A Common Stock at an offering price of $16.00 per share. On August 10, 2018, the underwriters exercised their right to purchase an additional 1,200,000 shares at the public offering price. The net offering proceeds, including the exercise of the over-allotment option, were $139.0 million, after deducting discount and offering expenses of $8.2 million. The Company used the proceeds to fund the ModSpace acquisition and to pay related fees and expenses. On August 15, 2018, WillScot issued 6,458,229 unregistered shares of its Class A Common Stock to former ModSpace shareholders as part of the consideration paid for ModSpace. In connection with the private placement, WillScot entered into a registration rights agreement dated July 26, 2018, under which WillScot granted customary registration rights to the holders of the unregistered common shares. Subject to limited exception, the unregistered shares issued to former ModSpace shareholders could not be sold or otherwise transferred prior to February 15, 2019. On December 11, 2018, pursuant to the terms of the Warrant Exchange discussed in more detail below, the Company issued 8,205,841 registered Class A common shares. In connection with the stock compensation vesting and stock option exercises described in Note 17, the Company issued 309,857 shares of Common Stock during the year ended December 31, 2019. On June 30, 2020, as contemplated by the Merger Agreement, Sapphire Holdings exchanged each of its shares of common stock of Holdings for 1.3261 shares of newly issued WillScot Class A Common Stock (the "Sapphire Exchange"). As a result of the Sapphire Exchange, all issued and outstanding shares of WillScot's Class B Common Stock, par value $0.0001 per share, were automatically canceled for no consideration and the existing exchange agreement was automatically terminated. As a result of the Sapphire Exchange, Sapphire Holdings became a wholly-owned subsidiary of WillScot. Sapphire Holdings received 10,641,182 shares of Common Stock of WillScot in the Sapphire Exchange. Prior to the Sapphire Exchange, Sapphire Holdings' ownership of Holdings was recorded as a non-controlling interest in the consolidated financial statements. Subsequent to the Sapphire Exchange, the Company's subsidiaries are each wholly owned and there is no non-controlling interest. As a result of the Sapphire Exchange, non-controlling interest of $63.9 million was reclassified to $66.9 million of additional paid-in-capital and $(3.0) million to accumulated other comprehensive loss, on the consolidated balance sheet. In connection with the Merger on July 1, 2020, the Company issued 106,426,722 shares of Class A Common Stock in exchange for Mobile Mini Common Stock outstanding and subsequently filed an amended and restated certificate of incorporation, which reclassified all outstanding shares of the Class A Common Stock and converted such shares into shares of Common Stock, par value of $0.0001 per share, of WillScot Mobile Mini. In connection with the Sapphire Exchange described above, stock compensation vesting and stock option exercises described in Note 17, and the warrant exercises described below, the Company issued 13,792,582 shares of Common Stock during the year ended December 31, 2020. Stock Repurchase Program On August 7, 2020, the Company's Board of Directors approved a stock repurchase program that authorizes the Company to repurchase up to $250 million of its outstanding shares of Common Stock and equivalents. The stock repurchase program does not obligate the Company to purchase any particular number of shares, and the timing and exact amount of any repurchases will depend on various factors, including market pricing, business, legal, accounting, and other considerations. The Company may repurchase its shares in open market transactions from time to time or through privately negotiated transactions in accordance with federal securities laws, at the Company's discretion. The repurchase program, which has no expiration date, may be increased, suspended, or terminated at any time. The program is expected to be implemented over the course of several years and will be conducted subject to the covenants in the agreements governing our indebtedness. During the year ended December 31, 2020, no shares of Common Stock were repurchased, and the Company repurchased $35.3 million warrants and share equivalents, including withholding taxes on net share settlements of employee stock awards. Warrants 2015 Public Warrants As part of its initial public offering, the Company issued warrants (the “Public W arrants”). Each Public Warrant entitled the holder to purchase one-half of one share of WillScot Class A Common Stock at a pric e of $5.75 per half share (or $11.50 pe r whole share), subject to adjustment. The Company was able to redeem the Public Warrants for $0.01 per warrant if the closing price of WillScot’s Class A shares equaled or exceeded $18.00 per share for any 20 trading days within a 30-trading day period ending on the third trading day prior to the date the Company sent a notice of redemption to the warrant holders, providing for a 30-day notice period. 2015 Public Warrant Exchange On November 8, 2018, WillScot commenced an offer to exchange the Public Warrants for shares of its Class A Common Stock in a cashless transaction (the “Warrant Exchange”). In the tender offer, each warrant holder had the opportunity to receive 0.18182 registered share of Class A Common Stock in exchange for each warrant tendered by the holder and exchanged pursuant to the offer. In connection, with the Warrant Exchange 45,131,827 of the outstanding 69,499,694 warrants were tendered and accepted for exchange and 8,205,841 shares of Class A Common Stock were issued. T he Company capitalized $1.8 million of offering expenses within additional paid-in capital in December 2018 in connection with the Warrant Exchange. As the fair value of the warrants ex changed in the Warrant Exchange offer was less than the fair value of the Common Stock issued, the Company recorded a non-cash deemed dividend of $2.1 million for the incremental fair value provided to the warrant holders. The fair value of the warrants was determined using the over-the-counter market price on December 7, 2018, a Level 2 fair value input. The fair value of the common stock was determined using the closing market price of the Company's common stock on December 7, 2018 , a Level 1 fair value input. 2015 Public Warrant Redemption The Company's share price performance target was achieved on January 21, 2020 and, on January 24, 2020, the Company delivered a notice (the "Redemption Notice") to redeem all of its Public Warrants that remained unexercised on February 24, 2020. As further described in the Redemption Notice and permitted under the warrant agreement, holders of these warrants who exercised them following the date of the Redemption Notice were required to do so on a cashless basis. From January 1, 2020 through January 24, 2020, 796,610 warrants were exercised for cash, resulting in the Company receiving cash proceeds of $4.6 million and the Company issuin g 398,305 sha res of the Company's Class A Common Stock. After January 24, 2020 through February 24, 2020, 5,836,048 warrants were exercised on a cashless basis. An aggregate of 1,097,162 shares of the Company's Class A Common Stock was issued in connection with these cashless exercises. Thereafter, the Company completed the redemption of 38,509 remaining warrants under the Redemption Notice for $0.01 per warrant. At December 31, 2020, no Public Warrants were outstanding. 2015 Private Warrants The Company also issued warrants to purchase its Common Stock in a private placement concurrently with its initial public offering (the “Private Warrants,” and together with the Public Warrants, the "2015 Warrants"). The Private Warrants were purchased at a price of $0.50 per unit for an aggregate purchase price of $9.75 million. The Private Warrants are identical to the Public Warrants, except that, if held by certain original investors (or their permitted assignees), the Private Warrants may be exercised on a cashless basis and are not subject to redemption. During the year ended December 31, 2020, 4,781,700 Private Warrants were repurchased for $21.6 million and cancelled. Additionally, 70,000 Private Warrants were exercised, resulting in the Company receiving cash proceeds of $0.4 million and issuing 35,000 shares of Common Stock. At December 31, 2020, 12,710,000 Private Warrants were outstanding. 2018 Warrants In connection with the ModSpace acquisition in 2018, WillScot issued warrants to purchase approximately 10.0 million WillScot Class A common shares (the "2018 Warrants") to former shareholders of ModSpace. Each 2018 Warrant entitles the holder thereof to purchase one share of WillScot Class A Common Stock at an exercise price of $15.50 per share, subject to potential adjustment. Subject to limited exception, the 2018 Warrants were not exercisable or transferable until February 11, 2019. The 2018 Warrants expire on November 29, 2022. Under a registration rights agreement dated July 26, 2018, WillScot agreed to file a registration statement by the six-month anniversary of the issuance date. The registration statement became effective February 12, 2019. During the year ended December 31, 2020, 195,410 2018 warrants were exercised, on a cashless basis, and 38,802 shares of the Company's Common Stock were issued. Also during the year ended December 31, 2020, the Company repurchased and subsequently cancelled 51,865 2018 warrants for approximately $0.3 million. At December 31, 2020, 9,730,241 2018 Warrants were outstanding. Accumulated Other Comprehen sive Loss The changes in accumulated other comprehensive loss ("AOCI"), net of tax, for the years ended December 31, 2020, 2019 and 2018, were as follows: (in thousands) Foreign Currency Translation Unrealized losses on hedging activities Total Balance at December 31, 2017 $ (49,497) $ — $ (49,497) Other comprehensive loss before reclassifications (11,639) (6,240) (17,879) Reclassifications from AOCI to income (a) — 285 285 Reclassifications from AOCI to retained earnings (b) (2,540) — (2,540) Less other comprehensive income attributable to non-controlling interest 1,068 537 1,605 Balance at December 31, 2018 (62,608) (5,418) (68,026) Other comprehensive income (loss) before reclassifications 10,586 (7,930) 2,656 Reclassifications from AOCI to income (a) — 3,121 3,121 Less other comprehensive income (loss) attributable to non-controlling interest (960) 434 (526) Balance at December 31, 2019 (52,982) (9,793) (62,775) Other comprehensive income (loss) before reclassifications 28,404 (11,874) 16,530 Reclassifications from AOCI to income (a) — 10,125 10,125 Less other comprehensive income attributable to non-controlling interest 1,183 702 1,885 Impact of elimination of non-controlling interest on accumulated other comprehensive income (1,299) (1,673) (2,972) Balance at December 31, 2020 $ (24,694) $ (12,513) $ (37,207) (a) For the years ended December 31, 2020, 2019 and 2018, $10.1 million, $3.3 million and $0.4 million, respectively, was reclas sified from AOCI into the consolidated statement of operations within interest expense related to the interest rate swaps discussed in Note 14. For the years ended December 31, 2020, 2019 and 2018 , the Company recorded a tax bene fit of $2.4 million, $0.8 million and $0.1 million associated with this reclassification, respectively. (b) In the first quarter of 2018, the Company elected to early adopt ASU 2018-02, Income Statement-Reporting Comprehensive Income (Topic 220) - Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income , which resulted in a discrete reclassification of $2.5 million from accumulated other comprehensive loss to accumulated deficit effective January 1, 2018.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The components of income tax (benefit) expense for the years ended December 31, 2020 , 2019 and 2018 are comprised of the following: (in thousands) 2020 2019 2018 US Federal and State Current $ 1,601 $ 827 $ 668 Deferred (58,026) 1,904 (36,149) Outside of US Current 2,104 (395) 924 Deferred 2,870 (4,527) (4,043) Total income tax benefit $ (51,451) $ (2,191) $ (38,600) Income tax results differed from the amount computed by applying the US statutory income tax rate of 21% to the income (loss) before income taxes for the following reasons for the years ended December 31, 2020 , 2019 and 2018: (in thousands) 2020 2019 2018 Income (loss) before income tax US $ 3,136 $ (9,477) $ (80,824) Non-US 17,292 (4,257) (11,348) Total income (loss) before income tax $ 20,428 $ (13,734) $ (92,172) US Federal statutory income tax expense (benefit) $ 4,290 $ (2,884) $ (19,356) Effect of tax rates in foreign jurisdictions 128 (207) (626) State income tax expense (benefit), net of federal benefit 3,962 1,829 (2,478) Unremitted foreign earnings — — (6,793) Valuation allowances (56,479) 961 (11,871) Non-deductible items 187 (233) — Non-deductible executive compensation 1,449 490 — Non-deductible transaction costs 4,425 (12) 1,134 Uncertain tax positions (11,166) — — Tax law changes (excluding valuation allowance) (a) 2,523 (2,785) 64 Other (770) 650 1,326 Reported income tax benefit $ (51,451) $ (2,191) $ (38,600) Effective income tax rate (251.87) % 15.95 % 41.88 % (a) Tax law changes include the following amounts: 2020 and 2019 primarily represents changes in tax law in non-US jurisdictions and 2018 primarily represents US tax reform items. Deferred Income Taxes Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities and their tax bases, as well as from net operating loss and carryforwards. Significant components of the Company’s deferred tax assets and liabilities are as follows: (in thousands) 2020 2019 Deferred tax assets Deferred interest expense $ 128,346 $ 138,206 Employee benefit plans 3,532 1,916 Accrued liabilities 10,692 8,494 Deferred revenue 32,412 20,951 Operating lease liability 58,044 37,438 Other 13,628 7,817 Tax loss carryforwards 295,326 231,503 Deferred tax assets, gross 541,980 446,325 Valuation allowance (25,158) (80,241) Net deferred income tax asset $ 516,822 $ 366,084 Deferred tax liabilities Rental equipment and other property, plant and equipment $ (648,966) $ (375,682) Intangible assets (117,403) (23,690) ROU asset (57,820) (37,218) Deferred tax liability (824,189) (436,590) Net deferred income tax liability $ (307,367) $ (70,506) In general, FASB ASC Section 740, “Income Taxes” (“ASC 740”) requires us to evaluate the realizability of our deferred tax assets and reduce the deferred tax assets by valuation allowances to the extent we determine some or all of our deferred tax assets are not more likely than not realizable. To determine the realizability, ASC 740 requires consideration of sources of available taxable income of the proper character and within the time period before which our deferred tax assets, if any, expire due to the passage of time. The Company's valuation allowance decreased by $55.1 million from 2019. An increase of $1.5 million was recorded in purchase accounting for the Merger in relation to state net operating losses deemed not more likely than not to be realized and a decrease in the change in estimate about the realizability of deferred tax assets for a total amount of $56.6 million was recorded as a tax benefit. Prior to the Merger, the Company's sources of taxable income were insufficient to realize a significant portion of WillScot's historical deferred tax assets. As a result, at December 31, 2019, the Company maintained valuation allowances of approximately $80.2 million to cover deferred tax assets that were not realizable. The significant WillScot historical deferred tax assets covered by valuation allowances were net operating losses and deferred interest expense. On July 1, 2020, with the Merger, estimates for future taxable income increased significantly; accordingly, the Company concluded that a substantial portion of WillScot's historical deferred tax assets that were previously covered by valuation allowances became more likely than not realizable. As a result, the Company reversed $54.6 million of valuation allowances as a discrete benefit in the third quarter of 2020 relating to the Merger. The significant deferred tax assets of the Company are comprised of net operating losses and deferred interest expense. A small percentage of the net operating losses are subject to an annual limitation based on tax law for which a valuation allowance continues to be maintained. Tax loss carryforwards at December 31, 2020 are outlined in the table below and include US Federal, US State and non-US (Mexico, Canada and UK). The availability of these tax losses to offset future income varies by jurisdiction. Furthermore, the ability to utilize the ta x losses may be subject to additional limitations upon the occurrence of certain events, such as a change in the ownership of the Company. The Company anticipates that our remaining available net operating losses will be consumed prior to their expiration. The Company’s tax loss carryforwards are as follows at December 31, 2020: (in thousands) Loss Expiration Jurisdiction: US - Federal $ 1,187,500 2022 – 2037, Indefinite US - State 700,500 2021 –2040, Indefinite Foreign - Mexico & Canada 14,100 2025 – 2038 Total $ 1,902,100 As of December 31, 2020, the total amount of the basis difference in investments outside the US, which are indefinitely reinvested and for which deferred taxes have not been provided, is approximately $327.3 million . The tax, if any, associated with the recovery of the basis difference is dependent on the manner in which it is recovered and is not readily determinable. Unrecognized Tax Positions The Company is subject to taxation in US, Canada, Mexico, UK, and state jurisdictions. The Company’s tax returns are subject to examination by the applicable tax authorities prior to the expiration of statute of limitations for assessing additional taxes, which generally ranges from two to five years after the end of the applicable tax year. Therefore, as of December 31, 2020 , tax years for 2014 through 2020 generally remain subject to examination by the tax authorities. In addition, in certain taxing jurisdictions, in the case of carryover tax attributes to years open for assessment, such attributes may be subject to reduction by taxing authorities. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: (in thousands) 2020 2019 2018 Unrecognized tax benefits – January 1, $ 63,747 $ 64,444 $ 72,660 Increases based on tax positions related to current period 1,211 — 1,545 Increases based on tax positions related to prior period — 268 — Decreases based on tax positions related to prior period — (287) (9,016) Decrease from expiration of statute of limitations (10,464) (678) (745) Unrecognized tax benefits – December 31, $ 54,494 $ 63,747 $ 64,444 At December 31, 2020, 2019 and 2018, respectively, there we re $53.2 million, $59.3 million and $60.0 million of unrecognized tax benefits that, if recognized, would affect the annual effective tax rate. The Company classifies interest on tax deficiencies and income tax penalties within income tax expense. During the years ended December 31, 2020, 2019 and 2018, the Company recognized approximately $(0.9) million, $0.8 million, and $1.0 million in interest and penalties, respectively. The Company had approximately $1.5 million and $2.4 million for the payment of interest and penalties accrued at December 31, 2020 and 2019, respectively. Future tax settlements or statute of limitation expirations could result in a change to the Company’s uncertain tax positions. The Company believes that it is reasonably possible that approximately $11.3 million of unrecognized tax benefits, as of December 31, 2020, could decrease in the next twelve months as a result of statute of limi tation expirations, audit settlements or resolution of tax uncertainties.

Derivatives

Derivatives	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	Derivatives On November 6, 2018, the Company entered into an interest rate swap agreement (the “Swap Agreement”) with a financial counterparty that effectively converts $400.0 million in aggregate notional amount of variable-rate debt under the Company’s ABL Facility into fixed-rate debt. The Swap Agreement will terminate on May 29, 2022. Under the terms of the Swap Agreement, the Company receives a floating rate equal to one-month LIBOR and makes payments based on a fixed rate of 3.06% on the notional amount. The receive rate under the terms of the Swap Agreement was 0.15% and 1.74% at December 31, 2020 and 2019, respectively. The Swap Agreement was designated and qualified as a hedge of the Company’s exposure to changes in interest payment cash flows created by fluctuations in variable interest rates on the ABL Facility. The location and the fair value of derivative instruments designated as hedges in the consolidated balance sheets as of December 31 was as follows: (in thousands) Balance Sheet Location 2020 2019 Cash Flow Hedges: Interest rate swap Accrued liabilities $ 11,619 $ 5,348 Interest rate swap Other non-current liabilities $ 5,308 $ 8,943 The fair value of the interest rate swap is based on dealer quotes of market forward rates, a Level 2 input on the fair value hierarchy, and reflects the amount that the Company would receive or pay as of December 31, 2020 for contracts involving the same attributes and maturity dates. The following table discloses the impact of the interest rate swap, excluding the impact of income taxes, on other comprehensive income (“OCI”), AOCI and the Company’s statement of operations for the years ended December 31: (in thousands) 2020 2019 2018 Loss recognized in OCI $ (2,288) $ (6,280) $ (7,777) Location of loss recognized in income Interest expense Interest expense Interest expense Loss reclassified from AOCI into income (effective portion) $ (10,125) $ (3,254) $ (373)

Fair Value Measures

Fair Value Measures	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measures	Fair Value Measures The fair value of financial assets and liabilities are included at the amount at which the instrument could be exchanged in a current transaction between willing parties, other than in a forced or liquidation sale. The Company utilizes the suggested accounting guidance for the three levels of inputs that may be used to measure fair value: Level 1 - Observable inputs such as quoted prices in active markets for identical assets or liabilities; Level 2 - Observable inputs, other than Level 1 inputs in active markets, that are observable either directly or indirectly; and Level 3 - Unobservable inputs for which there is little or no market data, which require the reporting entity to develop its own assumptions The Company has assessed that the fair value of cash and short-term deposits, trade receivables, trade payables, capital lease and other financing obligations, and other current liabilities approximate their carrying amounts. The following table shows the carrying amounts and fair values of financial assets and liabilities, including their levels in the fair value hierarchy: December 31, 2020 December 31, 2019 Carrying Amount Fair Value Carrying Amount Fair Value (in thousands) Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 US ABL Facilities (a) $ 1,263,833 $ — $ 1,304,612 $ — $ 885,245 $ — $ 903,000 $ — Multicurrency Facility (a) — $ — — — — — — — 2022 Secured Notes (a) — — — — 264,576 — 282,250 — 2023 Secured Notes (a) — — — — 482,768 — 517,334 — 2025 Secured Notes (a) 637,068 — 694,876 — — — — — 2028 Secured Notes (a) 491,555 — 518,820 — — — — — Total $ 2,392,456 $ — $ 2,518,308 $ — $ 1,632,589 $ — $ 1,702,584 $ — (a) The carrying values of the US ABL Facilities, the Multicurrency Facility, the 2025 Secured Notes, and the 2028 Secured Notes included $40.8 million, $0, $12.9 million, and $8.4 million of unamortized debt issuance costs as of December 31, 2020, which were presented as a direct reduction of the corresponding liability. The carrying values of the US ABL Facility, the Canadian ABL Facility, the 2022 Secured Notes, and the 2023 Secured Notes inclu ded $17.8 million, $0, $5.4 million, and $7.2 million of unamortized debt issuance costs at December 31, 2019, which were presented as a direct reduction of the corresponding liability. There were no tran sfers of financial instruments between the three levels of the fair value hierarchy during the years ended December 31, 2020 and 2019. The carrying value of the ABL Facility, excluding debt issuance costs, approximates fair value as the interest rates are variable and reflective of market rates. The fair value of the 2022 Secured Notes, the 2023 Secured Notes, the 2025 Secured Notes, and the 2028 Secured Notes is based on their last trading price at the end of each period obtained from a third party. The loca tion and the fair value of derivative assets and liabilities designated as hedges in the consolidated balance sheet are disclosed in Note 14. As part of the Merger, on July 2, 2020, the Company converted Mobile Mini's outstanding fully vested stock options to 7,361,516 WillScot Mobile Mini stock options using a conversion ratio of 2.405 as set by the Merger Agreement. The fair value of these options was valued at $19.3 million and is part of the purchase consideration. The value of the Mobile Mini stock options converted to WillScot Mobile Mini stock options in connection with the Merger, was determined utilizing the Black-Scholes option-pricing model and is affected by several variables, the most significant of which are the expected life of the equity award, the exercise price of the stock option as compared to the fair market value of the Common Stock on the Merger date, and the estimated volatility of the Common Stock over the term of the equity award. Estimated volatility is based on the historical volatility of the Company's Common Stock. The risk-free interest rate is based on the US Treasury yield curve in effect at the time of the Merger. The key inputs utilized to determine the fair value of the stock options converted included

Restructuring

Restructuring	12 Months Ended
	Dec. 31, 2020
Restructuring and Related Activities [Abstract]
Restructuring	Restructuring Restructuring costs include charges associated with exit or disposal activities that meet the definition of restructuring under FASB ASC Topic 420, Exit or Disposal Cost Obligations (“ASC 420”). The Company's restructuring plans are generally country or region specific and are typically completed within a one-year period. Restructuring costs incurred under these plans include (i) one-time termination benefits related to employee separations, (ii) contract termination costs, and (iii) other related costs associated with exit or disposal activities including, but not limited to, costs for consolidating or closing facilities. Lease exit costs related to the termination of leases for duplicative branches and corporate facilities are now recorded in operating lease liabilities and are not part of the restructuring liabilities. Costs related to the integration of acquired businesses that do not meet the definition of restructuring under ASC 420, such as employee training costs, duplicate facility costs, and professional services expenses, are included within SG&A expense. The Company incurred costs associated with restructuring plans designed to streamline operations and reduce costs of $6.5 million , $3.8 million, and $15.5 million net of reversals, during the years ended December 31, 2020 , 2019 and 2018, respectively. The following is a summary of the activity in the Company’s restructuring accruals for years ended December 31: (in thousands) Year Ended December 31, 2020 2019 2018 Employee Costs Facility Exit Costs Total Employee Costs Facility Exit Costs Total Employee Costs Facility Exit Costs Total Beginning balance $ 447 $ — $ 447 $ 4,544 $ 972 $ 5,516 $ 227 $ — $ 227 Reclassification of liability to operating lease asset at the adoption of ASC 842 (a) — — — — (972) (972) — — — Charges 6,510 17 6,527 1,955 1,800 3,755 10,182 5,286 15,468 Cash payments (5,356) — (5,356) (5,694) — (5,694) (5,806) (4,314) (10,120) Foreign currency translation 30 — 30 (136) — (136) (59) — (59) Non-cash movements 119 (17) 102 (222) (1,800) (2,022) — — — Ending balance $ 1,750 $ — $ 1,750 $ 447 $ — $ 447 $ 4,544 $ 972 $ 5,516 (a) As a result of the adoption of ASC 842, the January 1, 2019 restructuring liability attributable to “cease-use” locations was reclassified to operating lease assets and 2019 costs related to the termination of leases for duplicative branches and corporate facilities are now recorded in lease impairment charges and other related costs. The restructuring charges for the year ended December 31, 2020 are primarily driven by termination costs as a result of the elimination of positions due to the Merger and reductions in force as a result of COVID-19. The Company initiated certain restructuring plans associated with the ModSpace acquisition in order to capture operating synergies as a result of integrating ModSpace into WillScot. The restructuring activities primarily include the termination of employees in connection with the consolidation of overlapping facilities and functions within our existing business. The restructuring charges for the year ended December 31, 2018 primarily relate to employee termination costs and lease exist costs in connection with the integration of Acton, Tyson, and ModSpace acquisitions in order to capture operating synergies as a result of integrating these businesses into WillScot. The restructuring activities include the termination of leases for 26 duplicative branch and corporate facilities and the termination of employees in connection with the consolidation of these overlapping facilities and functions within our existing business. Segments (as defined in Note 19) The $6.5 million of restructuring charges for the year ended December 31, 2020 included: $2.1 million of charges pertaining to the NA Modular segment; $4.0 million of charges related to the NA Storage segment; and $0.4 million of charges related to the UK Storage segment. The $3.8 million of restructuring charges for the year ended December 31, 2019 included charges pertaining to the NA Modular segment. The $15.5 million of restructuring charges for the year ended December 31, 2018 included charges pertaining to the NA Modular segment.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation Restricted Stock Awards The following table summarizes the Company's RSA activity during the years ended December 31, 2020, 2019 and 2018 : Number of Shares Weighted-Average Grant Date Fair Value Balance, December 31, 2017 — $ — Granted 72,053 $ 15.57 Balance, December 31, 2018 72,053 $ 15.57 Granted 52,755 $ 14.69 Vested (72,053) $ 15.57 Balance, December 31, 2019 52,755 $ 14.69 Granted 65,959 $ 11.75 Vested (61,266) $ 14.28 Balance, December 31, 2020 57,448 $ 11.75 Compensation expense for RSAs recognized in SG&A expense in the consolidated statements of operations was $0.9 million, $1.0 million, and $0.5 million for the years ended December 31, 2020, 2019, and 2018, respectively. At December 31, 2020, there was $0.2 million of unrecognized compensation cost related to RSAs that was expected to be recognized over the remaining weighted average vesting period of 0.4 years. Time-Based RSUs The following table summarizes the Company's Time-Based RSU activity during the years ended December 31, 2020, 2019 and 2018 : Number of Shares Weighted-Average Grant Date Fair Value Balance, December 31, 2017 — $ — Granted 921,730 $ 13.60 Forfeited (68,997) $ 13.60 Balance, December 31, 2018 852,733 $ 13.60 Granted 478,400 $ 11.69 Forfeited (52,648) $ 12.78 Vested (213,180) $ 12.78 Balance, December 31, 2019 1,065,305 $ 12.78 Granted 632,864 $ 14.37 Forfeited (33,558) $ 13.28 Vested (538,845) $ 13.24 Balance, December 31, 2020 1,125,766 $ 13.44 Compensation expense for Time-Based RSUs recognized in SG&A expense in the consolidated statements of operati ons was $5.6 million, $3.9 million, and $2.3 million for the years ended December 31, 2020, 2019, and 2018, respectively. At December 31, 2020, unrecognized compensation cost related to Time-Based RSUs totaled $13.3 million and was expected to be recognized over the remaining weighted average vesting period of 2.7 years. Performance-Based RSUs The following table summarizes the Company's Performance-Based RSU award activity during the years ended December 31, 2020 and 2019 : Number of Shares Weighted-Average Grant Date Fair Value Balance, December 31, 2018 — $ — Granted 302,182 $ 13.22 Forfeited (13,901) $ 13.22 Balance, December 31, 2019 288,281 $ 13.22 Granted 325,256 $ 16.35 Forfeited (12,700) $ 14.70 Vested (7,449) $ 16.82 Balance, December 31, 2020 593,388 $ 14.88 Compensation expense for Performance-Based RSUs recognized in SG&A expense in the consolidated statements of operations wa s $2.5 million and $1.0 million for the years ended December 31, 2020 and 2019, respectively. For the year ended December 31, 2018, no compensation expense was recognized for Performance-Based RSUs. At December 31, 2020, unrecognized compensation cost related to Performance-Based RSUs totaled $5.4 million and was expected to be recognized over the remaining vesting period of 1.8 years. Performance-Based RSUs vest based on the Company’s TSR Percentile Ranking as compared against the TSR for the companies comprising the Russell 3000 Group, measured as of the end of the Performance Period, based on the performance goals set forth in the award agreement. Stock Options The following table summarizes the Company's stock option activity during the years ended December 31, 2020, 2019 and 2018 : WillScot Options Weighted-Average Exercise Price per Share Converted Weighted-Average Exercise Price per Share Outstanding options, December 31, 2017 — $ — — $ — Granted 589,257 $ 13.60 — $ — Outstanding options, December 31, 2018 589,257 $ 13.60 — $ — Forfeited (41,302) $ 13.60 — $ — Exercised (13,767) $ 13.60 — $ — Outstanding options, December 31, 2019 534,188 $ 13.60 — $ — Converted at Merger — $ — 7,361,516 $ 13.52 Exercised — $ — (428,653) $ 13.07 Cancelled in settlement, net of taxes — $ — (4,901,408) $ 13.04 Outstanding options, December 31, 2020 534,188 $ 13.60 2,031,455 $ 14.78 Fully vested and exercisable options, December 31, 2018 — $ — — $ — Vested during 2019 133,547 $ 13.60 — $ — Fully vested and exercisable options, December 31, 2019 133,547 $ 13.60 — $ — Vested during 2020 133,547 $ 13.60 2,031,455 $ 14.78 Fully vested and exercisable options, December 31, 2020 267,094 $ 13.60 2,031,455 $ 14.78 Under our stock option plans, the Company may issue shares on a net basis at the request of the option holder. This occurs by netting the option costs in shares from the shares exercised. No options were granted in the years ended December 31, 2020 or 2019. In the year ended December 31, 2018, the per share weighted-average fair value of all options grante d was $5.51 . At December 31, 2020, the intrinsic value of stock options outstanding and stock options fully vested and currently exercisable was $22.2 million and $19.6 million , respectively. At December 31, 2020, the weighted-average remaining contractual term of options outstanding was 7.2 years for WillScot options and 5.3 years for converted Mobile Mini options. The total intrinsic value of stock options exercised during the years ended December 31, 2020 and 2019 were $30.7 million and less than $0.1 million, respectively. No options were exercised during the year ended December 31, 2018. The total fair value of stock options vested during the years ended December 31, 2020 and 2019 was $31.8 million and $1.8 million, respectively. No stock options vested during the year ended December 31, 2018. WillScot Options Com pensation expense for stock option awards, recognized in SG&A expense in the consolidated statements of operations was $0.7 million, $0.8 million, and $0.6 million for the years ended December 31, 2020 , 2019, and 2018, respectively. At December 31, 2020, unrecognized compensation cost related to stock option awards totaled $0.9 million and is expected to be recognized over the remaining vesting period of 1.2 years. Conversion of Mobile Mini Options at the Merger As part of the Merger, on July 2, 2020 the Company converted Mobile Mini's outstanding fully vested stock options to 7,361,516 WillScot Mobile Mini stock options using a conversion ratio of 2.405 as set by the Merger Agreement. The fair value of these options was valued at $19.3 million and is part of the purchase consideration. The value of stock options converted was determined utilizing the Black-Scholes option-pricing model, and is affected by several variables, the most significant of which are the life of the equity award, the exercise price of the stock option as compared to the fair market value of the Common Stock on the Merger date, and the estimated volatility of the Common Stock over the term of the equity award. Estimated volatility is based on the historical volatility of the Company’s Common Stock. The risk-free interest rate is based on the US Treasury yield curve in effect at the time of the Merger.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments At December 31, 2020 and 2019, commitments for the acquisition of rental equipment and property, plant and equipment were $5.0 million and $4.5 million, res pectively. Contingencies - Legal Claims The Company is involved in various lawsuits or claims in the ordinary course of business. Management believes that there is no pending claim or lawsuit which, if adversely determined, would have a material effect on the Company’s financial condition, results of operations or cash flows.

Segment Reporting

Segment Reporting	12 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Segment Reporting	Segment Reporting As a result of the Merger, the Company has evaluated its operating structure and, accordingly, its segment structure and has determined it operates in four reportable segments as follows: North America Modular Solutions ("NA Modular"), North America Storage Solutions ("NA Storage"), United Kingdom Storage Solutions ("UK Storage") and Tank and Pump Solutions ("Tank and Pump"). The NA Modular segment aligns with the WillScot legacy business prior to the Merger and the NA Storage, UK Storage and Tank and Pump segments align with the Mobile Mini segments prior to the Merger. Total assets for each reportable segment are not available because the Company utilizes a centralized approach to working capital management. Transactions between reportable segments are not significant. In connection with the Merger, the Company determined its reportable segments as discussed above and retrospectively adjusted prior year's presentation to conform to the current presentation of reportable segments. The Company defines EBITDA as net income (loss) plus interest (income) expense, income tax (benefit) expense, depreciation and amortization. The Company reflects the further adjustments to EBITDA (“Adjusted EBITDA”) to exclude certain non-cash items and the effect of what the Company considers transactions or events not related to its core business operations. The Chief Operating Decision Maker ("CODM") evaluates business segment performance utilizing Adjusted EBITDA as shown in the reconciliation of the Company’s consolidated net income (loss) to Adjusted EBITDA below. Management believes that evaluating segment performance excluding such items is meaningful because it provides insight with respect to the intrinsic operating results of the Company. The Company also regularly evaluates gross profit by segment to assist in the assessment of its operational performance. The Company considers Adjusted EBITDA to be the more important metric because it more fully captures the business performance of the segments, inclusive of indirect costs. Reportable Segments The following tables set forth certain information regarding each of the Company’s reportable segments fo r the years ended December 31, 2020, 2019, and 2018, respectively. Consistent with the financial statements, the segment results only include results from Mobile Mini's operations after July 1, 2020, the Merger date. Please refer to the Management Discussion and Analysis of Financial Condition and Results of Operations included in this document, for pro forma results inclusive of Mobile Mini's financial results for periods prior to the Merger date. Year Ended December 31, 2020 (in thousands) NA Modular NA Storage UK Storage Tank and Pump Unallocated Costs Total Revenues: Leasing and services revenue: Leasing $ 770,330 $ 166,128 $ 32,633 $ 32,356 $ 1,001,447 Delivery and installation 208,079 42,655 9,409 14,013 274,156 Sales revenue: New units 41,858 6,976 3,124 1,135 53,093 Rental units 30,895 6,070 1,195 789 38,949 Total revenues 1,051,162 221,829 46,361 48,293 1,367,645 Costs: Cost of leasing and services: Leasing 194,442 19,925 7,391 5,618 227,376 Delivery and installation 175,705 27,029 6,353 11,015 220,102 Cost of sales: New units 27,555 4,244 2,301 741 34,841 Rental units 19,213 4,261 1,026 272 24,772 Depreciation of rental equipment 182,605 9,585 1,648 6,743 200,581 Gross profit $ 451,642 $ 156,785 $ 27,642 $ 23,904 $ 659,973 Other selected data: Adjusted EBITDA $ 394,805 $ 99,837 $ 17,822 $ 17,843 $ — $ 530,307 Selling, general and administrative expense (a) $ 242,010 $ 66,533 $ 11,468 $ 12,804 $ 91,864 $ 424,679 Purchases of rental equipment and refurbishments $ 153,327 $ 14,969 $ 1,693 $ 2,394 $ — $ 172,383 (a) Includes both SG&A expense and Transaction costs from the consolidated statement of operations. Year Ended December 31, 2019 (in thousands) NA Modular NA Storage UK Storage Tank and Pump Unallocated Costs Total Revenues: Leasing and services revenue: Leasing $ 744,185 $ — $ — $ — $ 744,185 Delivery and installation 220,057 — — — 220,057 Sales revenue: New units 59,085 — — — 59,085 Rental units 40,338 — — — 40,338 Total Revenues 1,063,665 — — — 1,063,665 Costs: Cost of leasing and services: Leasing 213,151 — — — 213,151 Delivery and installation 194,107 — — — 194,107 Cost of sales: New units 42,160 — — — 42,160 Rental units 26,255 — — — 26,255 Depreciation of rental equipment 174,679 — — — 174,679 Gross profit $ 413,313 $ — $ — $ — $ 413,313 Other selected data: Adjusted EBITDA $ 356,548 $ — $ — $ — $ — $ 356,548 Selling, general and administrative expense $ 235,228 $ — $ — $ — $ 35,776 $ 271,004 Purchases of rental equipment and refurbishments $ 205,106 $ — $ — $ — $ — $ 205,106 Year Ended December 31, 2018 (in thousands) NA Modular NA Storage UK Storage Tank and Pump Unallocated Costs Total Revenues: Leasing and services revenue: Leasing $ 518,235 $ — $ — $ — $ 518,235 Delivery and installation 154,557 — — — 154,557 Sales revenue: New units 53,603 — — — 53,603 Rental units 25,017 — — — 25,017 Total revenues 751,412 — — — 751,412 Costs: Cost of leasing and services: Leasing 143,120 — — — 143,120 Delivery and installation 143,950 — — — 143,950 Cost of sales: New units 36,863 — — — 36,863 Rental units 16,659 — — — 16,659 Depreciation of rental equipment 121,436 — — — 121,436 Gross profit $ 289,384 $ — $ — $ — $ 289,384 Other selected data: Adjusted EBITDA $ 215,533 $ — $ — $ — $ — $ 215,533 Selling, general and administrative expense (a) $ 200,895 $ — $ — $ — $ 53,976 $ 254,871 Purchase of rental equipment and refurbishments $ 160,883 $ — $ — $ — $ — $ 160,883 (a) Includes both SG&A expense and Transaction costs from the consolidated statement of operati ons. The following tables present a reconciliation of the Company’s net income (loss) to Adjusted EBITDA for the years ended December 31, 2020, 2019, and 2018, respectively: Year Ended December 31, (in thousands) 2020 2019 2018 Net income (loss) attributable to WillScot Mobile Mini $ 70,666 $ (11,122) $ (51,175) Net income (loss) attributable to non-controlling interest, net of tax 1,213 (421) (4,532) Non-cash deemed dividend related to warrant exchange — — 2,135 Loss on extinguishment of debt 42,401 8,755 — Income tax benefit (51,451) (2,191) (38,600) Interest expense 119,886 122,504 98,433 Depreciation and amortization 243,830 187,074 134,740 Currency (gains) losses, net (355) (688) 2,454 Goodwill and other impairment charges — 2,848 1,600 Restructuring costs, lease impairment expense and other related charges 11,403 12,429 15,468 Transaction costs 64,053 — 20,051 Integration costs 18,338 26,607 30,006 Stock compensation expense 9,879 6,686 3,439 Other 444 4,067 1,514 Adjusted EBITDA $ 530,307 $ 356,548 $ 215,533 Assets As discussed further in Note 2, the Company acquired Mobile Mini on July 1, 2020. The Company expects to finalize the valuation of the acquired net assets of Mobile Mini, including the final assignment of goodwill to reporting units, within the one-year measurement period from the date of acquisition. Assets related to the Company’s reportable segments include the following: (in thousands) NA Modular NA Storage UK Storage Tank and Pump Total As of December 31, 2020: Goodwill $ 235,828 $ 726,529 $ 65,600 $ 143,262 $ 1,171,219 Intangible assets, net $ 125,625 $ 329,437 $ 11,177 $ 29,708 $ 495,947 Rental equipment, net $ 1,888,287 $ 772,356 $ 147,720 $ 125,359 $ 2,933,722 As of December 31, 2019: Goodwill $ 235,177 $ — $ — $ — $ 235,177 Intangible assets, net $ 126,625 $ — $ — $ — $ 126,625 Rental equipment, net $ 1,944,436 $ — $ — $ — $ 1,944,436

Related Parties

Related Parties	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Parties	Related Parties Related party balances included in the Company’s consolidated balance sheets at December 31, consisted of the following: (in thousands) Financial statement line Item 2020 2019 Receivables due from affiliates Trade receivables, net of allowances for credit losses $ 30 $ 26 Amounts due to affiliates Accrued liabilities (461) (236) Total related party liabilities, net $ (431) $ (210) Related party transactions included in the Company’s consolidated statements of operations for the years ended December 31, consisted of the following: (in thousands) Financial statement line item 2020 2019 2018 Leasing revenue from related parties Leasing revenue $ 1,066 $ 316 $ 720 Rental unit sales to related parties Rental unit sales 380 — 1,548 Consulting expense to related party (a) Selling, general & administrative expense (5,194) (1,029) (3,070) Total related party expense, net $ (3,748) $ (713) $ (802) (a) Two of the Company's directors also serve on the Board of Directors of a consulting firm from which the Company incurs professional fees. On June 30, 2020, the Company completed the Sapphire Exchange, whereby Sapphire Holdings, an affiliate of TDR, exchanged shares of Class B Common Stock for 10,641,182 shares of Class A Common Stock. As a result of the Sapphire Exchange, all issued and outstanding shares of WillScot’s Class B Common Stock were automatically canceled for no consideration and the existing exchange agreement was automatically terminated. On August 22, 2018, WillScot’s majority stockholder, Sapphire Holdings, entered into a margin loan (the "Margin Loan") under which all of its WillScot Class A Common Stock was pledged to secure $125.0 million of borrowings under the loan agreement. WillScot is not a party to the loan agreement and has no obligations thereunder, but WillScot delivered an issuer agreement to the lenders under which WillScot has agreed to certain customary obligations relating to the shares pledged by Sapphire Holdings and, subject to applicable law and stock exchange rules, not to take any actions that are intended to materially hinder or delay the exercise of any remedies with respect to the pledged shares. In connection with the Margin Loan, on August 24, 2018, WSII entered into a two-year supply agreement with Target Logistics Management LLC, an affiliate controlled by Sapphire Holdings, under which, subject to limited exceptions, WSII acquired the exclusive right to supply modular units, portable storage units, and other ancillary products ordered by the affiliate in the US. On August 21, 2020, Sapphire Holdings entered into an amended and restated margin loan agreement which, among other things, extends the maturity date of the Margin Loan to August 29, 20 22. As of December 31, 2020, 59,725,558 shares of WillScot Mobile Mini Common Stock, representing approximately 26.1% of WillScot Mobile Mini’s issued and outstanding Common Stock, and 4,850,000 warrants exercisable for one half share of Common Stock were pledged by Sapphire Holdings under the Margin Loan. The two-year supply agreement with Target Logistics Managem ent LLC was not renewed. The Company purchased rental equipment from related party affiliates of $3.1 million, $4.7 million, and $4.3 million for the years ended December 31, 2020, 2019, and 2018, respectively.

Quarterly Financial Data

Quarterly Financial Data	12 Months Ended
	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data	Quarterly Financial Data The following tables present certain unaudited consolidated quarterly financial information for each of the eight quarters end ed December 31, 2020. In line with our filings with the SEC, prior to June 30, 2020, WillScot Mobile Mini refers to historical WillScot Corp. filed numbers. Post July 1, 2020, WillScot Mobile Mini refers to the combined company. (in thousands, except share and per share data) Quarter Ended (unaudited) 2020 March 31 June 30 September 30 December 31 Leasing and services revenue $ 239,422 $ 241,783 $ 384,776 $ 409,622 Total revenue $ 255,821 $ 256,862 $ 417,315 $ 437,647 Gross profit $ 106,190 $ 109,964 $ 209,564 $ 234,255 Operating income $ 25,373 $ 41,067 $ 25,012 $ 91,263 Net (loss) income $ (3,674) $ 12,833 $ 16,252 $ 46,468 Net (loss) income attributable to WillScot Mobile Mini $ (3,544) $ 11,490 $ 16,252 $ 46,468 (Loss) earnings per share - basic $ (0.03) $ 0.10 $ 0.07 $ 0.20 (Loss) earnings per share - diluted $ (0.03) $ 0.10 $ 0.07 $ 0.20 Weighted average shares - basic 109,656,646 110,692,426 226,649,993 228,637,826 Weighted average shares - diluted 109,656,646 111,432,963 231,216,573 236,696,853 (in thousands, except share and per share data) Quarter Ended (unaudited) 2019 March 31 June 30 September 30 December 31 Leasing and services revenue $ 227,292 $ 241,784 $ 249,411 $ 245,755 Total revenue $ 253,685 $ 263,713 $ 268,222 $ 278,045 Gross profit $ 103,331 $ 101,484 $ 99,307 $ 109,191 Operating income $ 21,464 $ 26,294 $ 29,781 $ 39,986 Net (loss) income $ (10,029) $ (11,438) $ 996 $ 8,928 Net (loss) income attributable to WillScot Mobile Mini $ (9,271) $ (10,606) $ 701 $ 8,054 (Loss) earnings per share - basic $ (0.09) $ (0.10) $ 0.01 $ 0.07 (Loss) earnings per share - diluted $ (0.09) $ (0.10) $ 0.01 $ 0.07 Weighted average shares - basic 108,523,269 108,693,924 108,720,857 108,793,847 Weighted average shares - diluted 108,523,269 108,693,924 112,043,866 114,080,059

Earnings (Loss) Per Share

Earnings (Loss) Per Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Earnings (Loss) Per Share	Loss) Per Share Basic earnings (loss) per share (“EPS”) is calculated by dividing net income (loss) attributable to WillScot Mobile Mini by the weighted average number of shares of Common Stock outstanding during the period. The shares of Common Stock issued as a result of the vesting of RSUs and RSAs as well as the exercise of stock options or redemption of warrants are included in EPS based on the weighted average number of days in which they were outstanding during the period. In 2018, 12,425,000 of WillScot's Class A common shares which had previously been held in escrow and excluded from the weighted average common shares calculation were released from escrow as follows: 6,212,500 of the escrowed shares were released to shareholders on January 19, 2018, and the remaining escrowed shares were released to shareholders on August 21, 2018. Prior to June 30, 2020, the Company had shares of Class B Common Stock which had no rights to dividends or distributions made by the Company and, in turn, were excluded from the EPS calculation. On June 30, 2020, the Sapphire Exchange was completed, and all shares of Class B Common Stock were cancelled, and Sapphire Holdings received 10,641,182 shares of Common Stock. Diluted EPS is computed similarly to basic EPS, except that it includes the potential dilution that could occur if dilutive securities were exercised. Effects of potentially dilutive securities are present ed only in periods in which they are dilutive. The following table reconciles the weighted average shares outstanding for the basic calculation to the weighted average shares outstanding for the diluted calculation for year ended December 31, 2020: (in thousands) December 31, 2020 Weighted average Common Shares outstanding - basic 169,230 Dilutive effect of outstanding securities: Warrants 3,116 RSAs 33 Time-Based RSUs 315 Performance-Based and Market-Based RSUs 322 Stock Options 634 Weighted average Common Shares outstanding - dilutive 173,650 The Company was in a net loss position for the years ended December 31, 2019 and 2018; therefore, no dilutive calculation was performed. For the year ended December 31, 2019, stock options, Time-Based RSUs, Market-Based RSUs, and RSAs representing 534,188, 1,065,305, 288,281, and 52,755 shares of Common Stock, respectively, were excluded from the computation of diluted EPS because their effect would have been anti-dilutive. Market-Based RSUs can vest at 0% to 150% of the amount granted. For the year ended December 31, 2018, stock options, Time-Based RSUs and RSAs, representing 589,257, 852,733 and 72,053 shares of Common Stock, respectively, were excluded from the computation of diluted EPS because their effect would have been anti-dilutive.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The consolidated financial statements were prepared in conformity with GAAP.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements comprise the financial statements of WillScot Mobile Mini and its subsidiaries that it controls due to ownership of a majority voting interest. Subsidiaries are fully consolidated from the date of acquisition, being the date on which the Company obtains control, and continue to be consolidated until the date when such control ceases. The financial statements of the subsidiaries are prepared for the same reporting period as WillScot Mobile Mini. All intercompany balances and transactions are eliminated.
Accounting Estimates	Accounting Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in these consolidated financial statements and accompanying notes. Actual results could differ from those estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid instruments with a maturity of three months or less when purchased to be cash equivalents. Trade Receivables and Allowance for Credit Losses
Trade Receivables and Allowance for Credit Losses	Trade Receivables and Allowance for Credit LossesThe Company is exposed to credit losses from trade receivables generated through its leasing and sales business. The Company assesses each customer’s ability to pay for the products it leases or sells by conducting a credit review. The credit review considers expected billing exposure and timing for payment and the customer’s established credit rating. The Company performs its credit review of new customers at inception of the customer relationship and for existing customers when the customer transacts new leases after a defined period of dormancy. The Company also considers contract terms and conditions, country risk and business strategy in the evaluation. The Company monitors ongoing credit exposure through an active review of customer balances against contract terms and due dates. The Company may employ collection agencies and legal counsel to pursue recovery of defaulted receivables. The allowances for credit losses reflect the estimate of the amount of receivables that the Company will be unable to collect based on historical write-off experience and, as applicable, current conditions and reasonable and supportable forecasts that affect collectability. This estimate could require change based on changing circumstances, including changes in the economy or in the particular circumstances of individual customers. Accordingly, the Company may be required to increase or decrease our allowances. In accordance with the adoption of Accounting Standards Update ("ASU") 2016-2, Leases (Topic 842) (" ASC 842"), effective January 1, 2019, and the adoption of ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) ("ASC 326"), effective January 1, 2020, specifically identifiable lease revenue receivables and sales receivables not deemed probable of collection are recorded as a reduction of revenue. The remaining provision for credit losses is recorded as selling, general and administrative expense. For the year ended December 31, 2018, the entire provision for credit losses was recorded as a selling, general and administrative expense. The Company reviews the adequacy of the allowance on a quarterly basis.
Concentration of Credit Risk	Concentration of Credit RiskThe Company’s trade accounts receivable subject the Company to potential concentrations of credit risk. The Company performs on-going credit evaluations of its customers. Receivables related to sales are generally secured by the product sold to the customer. The Company generally has the right to repossess its rental units in the event of non-payment of receivables relating to the Company’s leasing operations. The Company’s large number of customers in diverse geographic areas and end markets mitigates the concentration of credit risk.
Inventories	Inventories Inventories consist of raw materials, supplies, and finished units. Inventories are measured at the lower of cost or net realizable value based on the weighted-average cost. The cost includes expenditures incurred in acquiring the inventories, production or conversion costs, and other costs incurred in bringing them to their existing location and condition.
Property, Plant and Equipment	Rental Equipment Rental equipment is comprised of modular space and portable storage units held for rent or on rent to customers, tank and pump solutions products, which consist primarily of liquid and solid containment units, pumps and filtration equipment, and value-added products and services (“VAPS”) which are in use or available to be used by customers. Rental equipment is measured at cost less accumulated depreciation and impairment losses. Cost includes expenditures that are directly attributable to the acquisition of the asset. Costs of improvements and betterments to rental equipment are capitalized when such costs extend the useful life of the equipment or increase the rental value of the unit. Costs incurred for equipment to meet a particular customer specification are capitalized and depreciated over the lease term taking in consideration the residual value of the asset. Maintenance and repair costs are expensed as incurred. Depreciation is generally computed using the straight-line method over estimated useful lives, as follows: Estimated Useful Life Residual Value Modular space units 10 - 20 years 20 - 50% Portable storage units 30 years 55% Tank and pump equipment 7 - 25 years —% VAPS and other related rental equipment 1 - 8 years —% Property, Plant and Equipment Property, plant and equipment is measured at cost less accumulated depreciation and impairment losses. The Company capitalizes external costs and directly attributable internal costs to acquire or create internal use software incurred subsequent to the completion of the preliminary project stage. Costs associated with post-implementation activities are expensed as incurred. The Company evaluates implementation costs incurred in a cloud computing arrangement that is a service contract as described in Cloud Computing Arrangements below. Land is not depreciated. Leasehold improvements are amortized over the shorter of 15 years or the lease term. Assets leased under capital leases are depreciated over the shorter of the lease term or their useful life, unless it is reasonably certain that the Company will obtain ownership by the end of the lease term. Maintenance and repair costs are expensed as incurred. Depreciation is generally computed using the straight-line method over estimated useful lives as follows: Estimated Useful Life Buildings and leasehold improvements 10 - 40 years (a) Vehicles, machinery, and equipment 3 - 30 years Furniture and fixtures 3 - 10 years Software 3 - 10 years (a) Improvements to leased properties are depreciated over the lesser of the estimated useful life of the asset or the remaining term of the respective lease. Held for Sale Property, plant and equipment to be sold is classified as held for sale in the period in which: (i) the Company has approved and committed to a plan to sell the asset, (ii) the asset is available for immediate sale in its present condition, (iii) an active program to locate a buyer and other actions required to sell the asset have been initiated, (iv) the sale of the asset is probable, (v) the asset is being actively marketed for sale at a price that is reasonable in relation to its current fair value, and (vi) it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. Assets held for sale are initially measured at the lower of the carrying value or the fair value less cost to sell. Losses resulting from this measurement are recognized in the period in which the held for sale criteria are met while gains are not recognized until the date of sale. Once designated as held for sale, the Company stops recording depreciation expense on the asset. The Company assesses the fair value less cost to sell of long-lived assets held for sale at each reporting period until the assets no longer meet this classification. Impairment of Long-Lived Assets When circumstances indicate the carrying amount of long-lived assets in a held-for-use asset group may not be recoverable, the Company evaluates the assets for potential impairment using internal projections of undiscounted cash flows resulting from the use and eventual disposal of the assets. Events or changes in circumstances that may necessitate a recoverability evaluation include, but are not limited to, adverse changes in the regulatory environment or an expectation it is more likely than not that the asset will be disposed of before the end of its previously estimated useful life. If the carrying amount of the assets exceeds the undiscounted cash flows, an impairment expense is recognized for the amount by which the carrying amount of the asset group exceeds its fair value (subject to the carrying amount not being reduced below fair value for any individual long-lived asset that is determinable without undue cost and effort). Consistent with the provisions of ASC 842, the Company assesses whether any operating lease as set impairment exists in accordance with the measurement guidance in Accounting Standard Codification ("ASC") 360, Property Plant and Equipment .
Cloud Computing Arrangements	Cloud Computing Arrangements In accordance with ASU 2018-15, Goodwill and Other – Internal-Use Software (Subtopic 350-40) (“ASC 350-40"), t he Company evaluates implementation costs incurred in a cloud computing arrangement that is a service contract under the internal-use software framework. Costs related to preliminary project activities and post implementation activities are expensed as incurred. Costs incurred in the development stage are generally capitalized as other assets. Amortization expense is calculated on a straight-line basis over the contractual term of the cloud computing arrangement and recorded as selling, general and administrative expense. Capitalized implementation costs for cloud computing arrangements totale d $4.0 million a t December 31, 2020. The comparative financial statement information has not been restated and continues to be reported under the accounting standards in effect for those periods. The adoption of the guidance did not have a material impact on the Company's consolidated balance sheet as of January 1, 2020.
Goodwill and Goodwill Impairment	Goodwill and Goodwill Impairment For acquired businesses, the Company records assets acquired and liabilities assumed at their estimated fair values on the respective acquisition dates. Based on these values, the excess purchase price over the fair value of the net assets acquired is recorded as goodwill. Generally, reporting units are at the operating segment level or one level below the operating segment (the component level), if discrete financial information is prepared and regularly reviewed by segment management. Goodwill acquired in a business combination is assigned to each of the Company’s reporting units that are expected to benefit from the combination. The Company performs its annual impairment test of goodwill as of October 1 at the reporting unit level, as well as during any reporting period in which events or changes in circumstances occur that, in management’s judgment, may constitute triggering events under ASC 350-20, Intangibles – Goodwill and Other, Testing Goodwill for Impairment . The Company performs its assessment of goodwill utilizing either a qualitative or quantitative impairment test. The qualitative impairment test assesses company-specific, industry, market and general economic factors to determine whether it is more likely than not that the fair value of the reporting unit is less than its carrying amount. If the Company concludes that it is more likely than not that the fair value of the reporting unit is less than its carrying amount, or elects not to use the qualitative impairment test, a quantitative impairment test is performed. The quantitative impairment test involves a comparison of the estimated fair value of a reporting unit to its carrying amount. The Company uses an independent valuation specialist for its annual impairment tests to assist in the valuation. The Company has historically used the quantitative impairment test to evaluate goodwill for impairment. The Company used the qualitative approach for the reporting units acquired in the Merger due to the proximity of the July 1, 2020 acquisition date to the October 1, 2020 measurement date. Determining the fair value of a reporting unit is judgmental in nature and involves the use of significant estimates and assumptions. These estimates and assumptions include revenue growth rates and operating margins used to calculate projected future cash flows, risk-adjusted discount rates, value of net operating losses, future economic and market conditions and determination of appropriate market comparables. Management bases fair value estimates on assumptions it believes to be reasonable but that are unpredictable and inherently uncertain. Actual future results may differ from these estimates. If the carrying amount of the reporting unit exceeds the calculated fair value of the reporting unit, an impairment charge would be recognized for the excess, not to exceed the amount of goodwill allocated to that reporting unit.
Intangible Assets Other than Goodwill	Intangible Assets Other than Goodwill Intangible assets that are acquired by the Company and determined to have an indefinite useful life are not amortized but are tested for impairment at least annually. The Company’s indefinite-lived intangible assets consist of the Williams Scotsman trade name and the Mobile Mini trade name. The Company performs its assessment of indefinite-lived intangible assets utilizing either a qualitative or quantitative impairment test. When utilizing a quantitative impairment test, the Company calculates fair value using a relief-from-royalty method. This method is used to estimate the cost savings that accrue to the owner of an intangible asset who would otherwise have to pay royalties or license fees on revenues earned through the use of the asset. If the carrying amount of the indefinite-lived intangible asset exceeds its fair value, an impairment charge would be recorded to the extent the recorded indefinite-lived intangible asset exceeds the fair value.
Purchase Accounting	Purchase Accounting The Company accounts for acquisitions of businesses under the acquisition method. Under the acquisition method of accounting, the Company records assets acquired and liabilities assumed at their estimated fair value on the date of acquisition. Goodwill is measured as the excess of the fair value of the consideration transferred over the fair value of the identifiable net assets. Estimated fair values of acquired assets and liabilities are provisional and could change as additional information is received. When appropriate, our estimates of the fair values of assets and liabilities acquired include assistance from independent third-party valuation firms. Valuations are finalized as soon as practicable, but not later than one year from the acquisition date. Any subsequent changes to purchase price allocations result in a corresponding adjustment to goodwill.
Debt Issuance Costs	Debt Issuance Costs Debt issuance costs are recorded as direct deductions to the corresponding debt in long-term debt on the consolidated balance sheets. If no amounts are outstanding under the Company’s credit agreement as of a period end, the related debt issuance costs are recorded in other non-current assets in the consolidated balance sheets. Debt issuance costs are deferred and amortized to interest expense over the term of the respective debt using the effective interest method or straight-line interest method as appropriate.
Retirement Benefit Obligation	Retirement Benefit ObligationThe Company provides benefits to certain of its employees under defined contribution benefit plans. The Company’s contributions to these plans are generally based on a percentage of employee compensation or employee contributions. These plans are funded on a current basis. For its US and Canada employees, the Company sponsors defined contribution benefit plans that have discretionary matching contribution and profit-sharing features.
Stock-Based Compensation	Stock-Based Compensation Prior to the Merger, stock awards were granted under the WillScot Corporation 2017 Incentive Award Plan (the "2017 Incentive Plan"), which included Restricted Stock Awards ("RSAs") and Restricted Stock Units ("RSUs"). On June 24, 2020, WillScot's stockholders approved the WillScot Mobile Mini 2020 Incentive Award Plan ("2020 Incentive Plan") to take effect pending completion of the Merger. The plan amended and restated in its entirety the 2017 Incentive Plan. As a result, all historical and future incentive awards to the Company's Board of Directors, executive officers and employees, as determined by the Company's Compensation Committee ("the Comp Committee"), are granted under the 2020 Incentive Plan. The 2020 Incentive Plan is administered by the Comp Committee. Under the 2020 Incentive Plan, the Comp Committee may grant an aggreg ate of 6,488,988 shares of Common Stock in the form of non-qualified stock options, incentive stock options, stock appreciation rights, RSAs, RSUs, performance compensation awards and stock bonus awards. Stock-based payments, including the grant of stock options, RSAs and RSUs, are subject to service-based vesting requirements, and expense is recognized on a straight-line basis over the vesting period. Forfeitures are accounted for as they occur. Stock-based compensation expense includes grants of stock options, time-based RSUs ("Time-Based RSUs") and performance-based RSUs ("Performance-Based RSUs", together with Time-Based RSUs, the "RSUs"). The 2020 Incentive Plan continues the former Market-Based RSUs renamed as "Performance-Based RSUs." RSUs are recognized in the financial statements based on their fair value. In addition, stock-based payments to non-executive directors include grants of RSAs. Time-Based RSUs and RSAs are valued based on the intrinsic value of the difference between the exercise price, if any, of the award and the fair market value of WillScot Mobile Mini's Common Stock on the grant date. Performance-Based RSUs are valued based on a Monte Carlo simulation model to reflect the impact of the Performance-Based RSUs market condition. The probability of satisfying a market condition is considered in the estimation of the grant-date fair value for Performance-Based RSUs and the compensation cost is not reversed if the market condition is not achieved, provided the requisite service has been provided. RSAs cliff vest in a one year period. Time-Based RSUs vest ratably over a period of four years. Performance-Based RSUs cliff vest based on achievement of the relative total stockholder return ("TSR") of the Company's Common Stock as compared to the TSR of the constituents of the Russell 3000 Index at the grant date over the performance period of three years. The target number of RSUs may be adjusted from 0% to 150% based on the TSR attainment levels defined by the Comp Committee. The 100% target payout is tied to performance at the 50% percentile, with a payout curve ranging from 0% (for performance less than the 25% percentile) to 150% (for performance at or above the 75% percentile). Vesting is also subject to continued service requirements through the vesting date. Stock options vest in tranches over a period of four years and expire ten years from the grant date. The fair value of each stock option award on the grant date is estimated using the Black-Scholes option-pricing model with the following assumptions: expected dividend yield, expected stock price volatility, weighted-average risk-free interest rate and weighted-average expected term of the options. The volatility assumption used in the Black-Scholes option-pricing model was based on a blend of peer group volatility and Company trading history as the Company did not have a sufficient trading history as a stand-alone public company. Future calculations will use the Company trading history. Additionally, due to an insufficient history with respect to stock option activity and post-vesting cancellations, the expected term assumption is based on the simplified method under GAAP, which is based on the vesting period and contractual term for each tranche of awards. The mid-point between the weighted-average vesting term and the expiration date is used as the expected term under this method. The risk-free interest rate used in the Black-Scholes model is based on the implied US Treasury bill yield curve at the date of grant with a remaining term equal to the Company’s expected term assumption. WillScot Mobile Mini has never declared or paid a cash dividend on common shares.
Foreign Currency Translation and Transactions	Foreign Currency Translation and Transactions The Company’s reporting currency is the US Dollar (“USD”). Exchange rate adjustments resulting from foreign currency transactions are recognized in profit or loss, whereas effects resulting from the translation of financial statements are reflected as a component of accumulated other comprehensive loss, which is a component of shareholders’ equity. The assets and liabilities of subsidiaries whose functional currency is different from the USD are translated into USD at exchange rates at the reporting date and income and expenses are translated using average exchange rates for the respective period. Exchange rate adjustments resulting from transactions in foreign currencies (currencies other than the Company entities’ functional currencies) are remeasured to the respective functional currencies using exchange rates at the dates of the transactions and are recognized in currency (gains) losses on the consolidated statements of operations.
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities The Company utilizes derivative financial instruments, specifically interest rate swaps, to manage its exposure to fluctuations in interest rates on variable rate debt. The Company does not use derivatives for trading or speculative purposes. The Company records derivatives on the balance sheet at fair value within prepaid expenses and other current assets and other non-current assets (if in an unrealized gain position) or within accrued liabilities and other non-current liabilities (if in an unrealized loss position). If a derivative is designated as a cash flow hedge and meets the highly effective threshold, the changes in the fair value of derivatives are recorded in accumulated other comprehensive income (loss). Amounts reported in accumulated other comprehensive income (loss) related to the cash flow hedges are reclassified to earnings within interest expense when the hedged item impacts earnings. For any derivative instruments not designated as hedging instruments, changes in fair value would be recognized in earnings within interest expense in the period that the change occurs. Cash flows from derivative instruments are presented within net cash provided by operating activities in the consolidated statements of cash flows. The Company assesses, both at the inception of the hedge and on an ongoing quarterly basis, whether the derivatives designated as cash flow hedges are highly effective in offsetting the changes in cash flows of the hedged items. The use of derivative financial instruments carries certain risks, including the risk that the counterparties to these contractual arrangements are not able to perform under the agreements. To mitigate this risk, the Company enters into derivative financial ins truments only with counterparties with high credit ratings and with major financial institutions. The Company does not anticipate that any of the counterparties will fail to meet their obligations.
Revenue Recognition and Shipping Costs	Revenue Recognition A performance obligation is a promise in a contract to transfer a distinct good or service to the customer. A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. Leasing and Services Revenue The majority of revenue is generated by rental income subject to the guidance of ASC 840, Leases ("ASC 840") in 2018 and ASC 842 in 2019 and 2020. The remaining revenue is generated by performance obligations in contracts with customers for services or sale of units subject to the guidance in ASC 605, Revenue ("ASC 605"), in 2018 and Accounting Standards Update ("ASU") 2014-09, Revenue from Contracts with Customers (Topic 606) ("ASC 606") in 2019 and 2020. Leasing Revenue Income from operating leases is recognized on a straight-line basis over the lease term. The Company's lease arrangements can include multiple lease and non-lease components. Examples of lease components include, but are not limited to, the lease of modular space, portable storage units and VAPS. Examples of non-lease components include, but are not limited to, the delivery, install ation, maintenance, and removal services commonly provided in a bundled transaction with the lease components. Arrangement consideration is allocated between lease deliverables and non-lease components based on the relative estimated selling (leasing) price of each deliverable. Estimated selling (leasing) price of the lease deliverables is based upon the estimated stand-alone selling price of the related performance obligations using an adjusted market approach. When leases and services are billed in advance, recognition of revenue is deferred until services are rendered. If equipment is returned prior to the contractually obligated period, the excess, if any, between the amount the customer is contractually required to pay over the cumulative amount of revenue recognized to date is recognized as incremental revenue upon return. Rental equipment is leased primarily under operating leases and, from time to time, under sales-type lease arrangements. Operating lease minimum contractual terms within the NA Modular segment, as defined in Note 19, generally range from 1 month to 60 months and averaged approximately 9 months across this segment's rental fleet for the year ended December 31, 2020. Rental contracts with customers within the NA Storage and UK Storage segments are generally based on a 28-day rate and billing cycle. The rental continues until cancelled by the Company or the customer. T here were no material sales-type lease arrangements as of December 31, 2020 or 2019. The Company may use third parties to satisfy its performance obligations, including both the provision of rental units and other services. To determine whether it is the principal or agent in the arrangement, the Company reviews each third-party relationship on a contract-by-contract basis. The Company is considered an agent when its role is to arrange for another entity to provide the rental units and other services to the customer. In these instances, the Company does not control the rental unit or service before it is provided. The Company is considered the principal when it controls the rental unit or service prior to transferring control to the customer. WillScot Mobile Mini may be a principal in the fulfillment of some rental units and services and an agent for other rental units and services within the same contract. Revenue is recognized on a gross basis when the Company is the principal in the arrangement and on a net basis when it is the agent. The adoption of ASC 842 at January 1, 2019, did not have a significant impact on the recognition of leasing revenue. Based on the requirements of ASC 842, the Company records changes in estimated collectability, directly against leasing revenue. Services Revenue The Company generally has three non-lease service-related performance obligations in its contracts with customers: • Delivery and installation of the modular or portable storage unit; • Maintenance and other ad hoc services performed during the lease term; and • Removal services that occur at the end of the lease term. Consideration is allocated to each of these performance obligations within the contract based upon their estimated relative standalone selling prices using the estimated cost plus a margin approach. Revenue from these activities is recognized as the services are performed. Sales Revenue Sales revenue is generated by the sale of new and rental units. Revenue from the sale of new and rental units is generally recognized at a point in time upon the transfer of control to the customer, which occurs when the unit is delivered and installed in accordance with the contract. Sales transactions constitute a single performance obligation. Other Matters The Company's non-lease revenues do not include material amounts of variable consideration, other than the variability noted for services arrangements expected to be performed beyond a twelve-month period. The Company's payment terms vary by the type and location of its customer and the product or services offered. The time between invoicing and when payment is due is not significant. While the Company may bill certain customers in advance, its contracts do not contain a significant financing component based on the short length of time between upfront billings and the performance of contracted services. For certain products, services, or customer types, the Company requires payment before the products or services are delivered to the customer. Revenue is recognized net of taxes collected from customers, which are subsequently remitted to governmental authorities. Shipping Costs The Company includes third-party costs to deliver rental equipment to customers in costs of leasing and services, and cost of sales.
Leases as Lessee	Leases as Lessee The Company leases real estate for certain of its branch offices, administrative offices, rental equipment storage properties, vehicles and equipment, and administrative operations. The Company determines if an arrangement is or contains a lease at inception. Leases are classified as either finance or operating at inception of the lease, with classification affecting the pattern of expense recognition in the income statement. Short-term leases, defined as leases with an initial term of 12 months or less, are not recorded on the balance sheet. Lease expense for short-term leases is recognized on a straight-line basis over the lease term. The Company has leases that contain both lease and non-lease components and has elected, as an accounting policy, to not separate lease components and non-lease components. Operating and finance lease right of use ("ROU") assets and liabilities are recognized at the commencement date based on the present value of lease payments over the lease term. The lease liability is calculated as the present value of the remaining minimum rental payments for existing leases using either the rate implicit in the lease or, if none exists, the Company's incremental borrowing rate, as the discount rate. The Company uses its incremental borrowing rate at commencement date in determining the present value of lease payments for those leases where the implicit rate is not known. The Company's incremental borrowing rate is a hypothetical rate based on its understanding of what would be the Company's secured credit rating. Variable lease payments are expensed in the period in which the obligation for those payments is incurred. Variable lease payments include payments for common area maintenance, real estate taxes, management fees and insurance. 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 the Company is reasonably certain it will exercise the option. Many of these leases include one or more options to renew. Additionally, the Comp any’s leases do not generally include options to terminate the lease prior to the end of the lease term. The Company’s lease agreements do not contain any material residual value guarantees or material restrictive covenants.
Advertising and Promotion	Advertising and Promotion Advertising and promotion costs, which are expensed as incurred, were $7.3 million , $4.0 million and $4.4 million for the years ended December 31, 2020, 2019 and 2018, respectively.
Income Taxes	Income Taxes The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined based on the differences between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. The Company records deferred tax assets to the extent it believes that it is more likely than not that these assets will be realized. In making such determination, the Company considers all available positive and negative evidence, including scheduled reversals of deferred tax liabilities, projected future taxable income, tax planning strategies and recent results of operations. Valuation allowances are recorded to reduce the deferred tax assets to an amount that will more likely than not be realized. The Company assesses the likelihood that each of the deferred tax assets will be realized. To the extent management believes realization of any deferred tax assets is not likely, the Company establishes a valuation allowance. When a valuation allowance is established or there is an increase in an allowance in a reporting period, tax expense is generally recorded in the Company’s consolidated statement of operations. Conversely, to the extent circumstances indicate that a valuation allowance is no longer necessary, that portion of the valuation allowance is reversed, which generally reduces the Company’s income tax expense. Deferred tax liabilities are recognized for the income taxes on the undistributed earnings of wholly-owned foreign subsidiaries unless such earnings are indefinitely reinvested, or will only be repatriated when possible to do so at minimal additional tax cost. Current income tax relating to items recognized directly in equity is recognized in equity and not in profit (loss) for the year. In accordance with applicable authoritative guidance, the Company accounts for uncertain income tax positions using a benefit recognition model with a two-step approach; a more-likely-than-not recognition criterion; and a measurement approach that measures the position as the largest amount of tax benefit that is greater than 50% likely of being realized upon ultimate settlement. If it is not more-likely-than-not that the benefit of the tax position will be sustained on its technical merits, no benefit is recorded. Uncertain tax positions that relate only to timing of when an item is included on a tax return are considered to have met the recognition threshold. The Company classifies interest on tax deficiencies and income tax penalties within income tax expense. The Company accounts for any impacts of the Global Intangible Low-Taxed Income ("GILTI") in the period in which they are incurred.
Fair Value Measurements	Fair Value Measurements The Company maximizes the use of observable inputs and minimizes the use of unobservable inputs when measuring fair value. A financial instrument’s categorization within the fair value hierarchy is based upon the lowest level of input that is significant to the fair va lue measurement. The inputs are prioritized into three levels that may be used to measure fair value. See further discussion of the levels in Note 15.
Recently Issued and Adopted Accounting Standards	Recently Issued and Adopted Accounting Standards The Company qualified as an emerging growth company (“EGC”) as defined under the Jumpstart Our Business Startups Act (the “JOBS A ct”) until December 31, 2019. Using exemptions provided under the JOBS Act, the Company elected to defer compliance with new or revised financial accounting standards until a company that is not an issuer (as defined under section 2(a) of the Sarbanes-Oxley Act) was required to comply with such standards. WillScot ceased to be an EGC as of December 31, 2019, and as such, is required to comply with the standards and compliance dates for large accelerated filers. Recently Issued Accounting Standards In December 2019, the Financial Accounting Standards Board ("FASB") issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes , which simplifies the accounting for income taxes by removing certain exceptions to the general principles for income taxes. The new standard is effective for fiscal years and interim periods within those fiscal years, beginning after December 15, 2020. The Company is currently evaluating the potential impact of adoption of the pronouncement on its consolidated financial statements and does not expect the impact to be material. In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848) , which is elective, and provides for optional expedients and exceptions for applying GAAP to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. The Company is currently evaluating the impact of reference rate reform and potential impact of adoption of these elective practical expedients on its consolidated financial statements and does not expect the impact to be material. Recently Adopted Accounting Standards From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that are adopted by the Company as of the specified effective date. ASU 2014-09: Revenue from Contracts with Customers (Topic 606) In May 2014, the FASB issued ASC 606. ASC 606, along with its subsequent related updates prescribe a single comprehensive model for entities to use in the accounting for revenue arising from contracts with customers. The core principle contemplated by this new standard was that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount reflecting the consideration to which the entity expects to be entitled in exchange for those goods or services. New disclosures about the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers are also required. On January 1, 2019, the Company adopted ASC 606 as well as subsequent updates using the modified retrospective transition approach to those contracts that were not completed as of January 1, 2019. The comparative financial statement information has not been restated and continues to be reported under the accounting standards in effect for those periods. The adoption of the guidance did not have a material impact on the Company's consolidated balance sheet as of January 1, 2019. The Company's accounting for modular leasing revenue is primarily outside the scope of ASC 606 and is recorded under ASC 842. ASU 2016-02, Leases (Topic 842) In February 2016, the FASB issued ASC 842. This guidance revises existing practice related to accounting for leases under ASC 840, for both lessees and lessors. ASC 842 requires that lessees recognize: a) a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and b) a 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. ASC 842 also requires that the seller recognize any gain or loss (based on the estimated fair value of the asset at the time of sale) when control of the asset is transferred instead of amortizing it over the lease period for qualifying sale-leaseback transactions. Effective January 1, 2019, the Company retrospectively adopted ASC 842. In connection with the adoption of ASC 842, the Company reversed the previous accounting for certain failed sale-leaseback transactions, and reduced property, plant and equipment by $31.0 million, reduced outstanding debt by $37.9 million, increased deferred tax liability by $1.8 million and increased January 1, 2019 equity by $5.2 million. The Company recognized lease liabilities and ROU assets of $138.5 million and $141.4 million as of January 1, 2019, primarily related to its real estate and equipment leases. The comparative financial statement information has not been restated and continues to be reported under the accounting standards in effect for those periods. The adoption of ASC 842 at January 1, 2019, did not have a significant impact on the recognition of leasing revenue. Per the requirements of ASC 842 the Company records changes in estimated collectability, directly against lease revenue. Such amounts were previously classified as selling, general and administrative expenses. The Company elected the package of practical expedients permitted under the transition guidance within the new standard that allows it to not reassess: (a) whether any expired or existing contracts are or contain leases, (b) the lease classification for any expired or existing leases and (c) initial direct costs for any expired or existing leases. Historical financial information was not updated, and the financial disclosures required under ASC 842 are not provided for periods prior to January 1, 2019. ASU 2016-13: Financial Instruments - Credit Losses (Topic 326) In June 2016, the FASB issued ASC 326, which prescribes that financial assets (or a group of financial assets) should be measured at amortized cost basis to be presented at the net amount expected to be collected based on relevant historical information from historical experience, adjusted for current conditions and reasonable and supportable forecasts that affect collectability. Credit losses relating to these financial assets are recorded through an allowance for credit losses. The Company adopted ASC 326 effective January 1, 2020. The effect of this guidance was immaterial to the Company's consolidated results of operations, financial position and cash flows. ASU 2018-15, Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-40) In August 2018, the FASB issued ASC 350-40, which provides guidance on accounting for implementation costs incurred in a cloud computing arrangement that is a service contract. The amendments in this update align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software and hosting arrangements that include an internal-use software license. This guidance also requires entities to present the expense related to capitalized implementation costs in the same line item in the statement of operations as the fees associated with the hosting element (service) of the arrangement and classify payments for capitalized implementation costs in the statement of cash flows in the same manner as payments made for fees associated with the hosting element. The entity is also required to present the capitalized implementation costs in the balance sheet in the same line item that a prepayment for the fees of the associated hosting arrangement would be presented. The Company adopted ASC 350-40 on a prospective basis effective January 1, 2020. As a result of the adoption, capitalized implementation costs incurred in cloud computing arrangements were capitalized in other non-current assets in the consolidated balance sheet. The impact of this guidance did not materially impact the consolidated financial statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Activity in Allowance for Credit Losses	Activity in the allowance for credit losses for the years ended December 31 was as follows: (in thousands) 2020 2019 2018 Balance at beginning of year $ 15,828 $ 9,340 $ 4,845 Provision for credit losses, net of recoveries (a) 31,386 14,496 7,656 Write-offs (18,034) (7,945) (3,089) Foreign currency translation and other 78 (63) (72) Balance at end of period $ 29,258 $ 15,828 $ 9,340 (a) For the years ended December 31, 2020 and 2019, the provision for credit losses includes $18.0 million and $10.0 million, respectively, recorded as a reduction to revenue for the provision of specific receivables whose collection is not considered probable.
Schedule of Property, Plant and Equipment	Depreciation is generally computed using the straight-line method over estimated useful lives, as follows: Estimated Useful Life Residual Value Modular space units 10 - 20 years 20 - 50% Portable storage units 30 years 55% Tank and pump equipment 7 - 25 years —% VAPS and other related rental equipment 1 - 8 years —% Depreciation is generally computed using the straight-line method over estimated useful lives as follows: Estimated Useful Life Buildings and leasehold improvements 10 - 40 years (a) Vehicles, machinery, and equipment 3 - 30 years Furniture and fixtures 3 - 10 years Software 3 - 10 years (a) Improvements to leased properties are depreciated over the lesser of the estimated useful life of the asset or the remaining term of the respective lease. Rental equipment, net at December 31 consisted of the following: (in thousands) 2020 2019 Modular space units $ 2,520,704 $ 2,372,069 Portable storage units 931,363 83,402 Tank and pump products 132,071 — Value added products 143,652 121,855 Total rental equipment 3,727,790 2,577,326 Less: accumulated depreciation (794,068) (632,890) Rental equipment, net $ 2,933,722 $ 1,944,436 Property, plant and equipment, net at December 31 consisted of the following: (in thousands) 2020 2019 Land, buildings, and leasehold improvements $ 154,210 $ 139,861 Vehicles, machinery, and office equipment 227,009 62,169 Software and other 20,800 27,342 Total property, plant and equipment 402,019 229,372 Less: accumulated depreciation (98,369) (81,683) Property, plant and equipment, net $ 303,650 $ 147,689

Business Combinations and Acq_2

Business Combinations and Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2020
Business Combinations [Abstract]
Schedule of Business Combination
Business Combination, Pro Forma Information	The following table summarizes the key inputs utilized to determine the fair value of the Stock Consideration and 2018 Warrants included within the purchase price of ModSpace. Stock Consideration 2018 Warrants fair value inputs Expected volatility 28.6 % 35.0 % Risk-free rate of interest 2.2 % 2.7 % Dividend Yield — % — % Expected life (years) 0.5 4.3 The pro forma information does not reflect any cost savings from operating efficiencies or synergies that could result from the acquisition, and also does not reflect additional revenue opportunities following the acquisition. (unaudited, in thousands) Year Ended December 31, 2018 (a) WillScot revenues $ 751,412 ModSpace revenues 312,609 Pro forma revenues $ 1,064,021 WillScot loss from operations before income tax $ (92,172) ModSpace loss from operations before income tax (7,457) Loss from operations before income tax before pro forma adjustments (99,629) Pro forma adjustments to combined loss from operations before income tax: Impact of fair value adjustments/useful life changes on depreciation 10,135 Intangible asset amortization (625) (b) Interest expense (41,178) (c) Elimination of ModSpace interest 20,279 (d) Pro forma loss from operations before income tax (111,018) (e) Income tax benefit (43,462) (f) Pro forma net loss $ (67,556) (a) Pro forma results for the year ended December 31, 2018 include ModSpace historical activity. Post-acquisition ModSpace revenues and pre-tax income are reflected in the Company's historical revenue and pre-tax income amounts. (b) Amortization of the trade names acquired. The ModSpace trade name was assigned a value of $3.0 million and a life of three years. (c) In connection with the ModSpace acquisition, the Company drew an incremental $419.0 million on the ABL Facility and issued $300.0 million of 2023 Secured Notes and $200.0 million of unsecured notes. An interest rate of 6.54% was used to calculate pro forma interest expense as a result of the ModSpace acquisition, which represents the weighted-average interest rate for the aforementioned borrowings at December 31, 2018. Interest expense includes amortization of related deferred financing fees on debt incurred in conjunction with the ModSpace acquisition. (d) Interest on ModSpace historical debt was eliminated. (e) Pro forma loss from operations before income taxes includes $15.5 million of restructuring expense, $30.0 million of integration costs, and $20.1 million of transaction costs incurred by WillScot for the year ended December 31, 2018. Additionally, pro forma pre-tax loss for the year ended December 31, 2018 also includes $20.5 million of interest expense associated with bridge financing fees incurred in connection with the acquisition of ModSpace. (f) As the combined pro forma company was in a tax loss position in 2018, all pro forma adjustments for US tax effects are at the federal and state US statutory tax rate of 25.8% since the adjustments represent future deductible or taxable temporary differences. Mobile Mini Merger On March 1, 2020, the Company, along with its newly formed subsidiary, Merger Sub, entered into the Merger Agreement with Mobile Mini, hereby referred to as the “Merger”. The Merger was completed on July 1, 2020 and Merger Sub merged with and into Mobile Mini and the separate corporate existence of Merger Sub ceased, and Mobile Mini continued its existence as the surviving corporation in the Merger and a wholly-owned subsidiary of the Company. Mobile Mini is a leading provider of portable storage solutions in North America and the UK and a leading provider of specialty containment solutions in the US. Purchase Price Upon completion of the Merger, each issued and outstanding share of Mobile Mini Common Stock, par value $0.01 per share, converted to 2.405 shares of WillScot Class A Common Stock, par value $0.0001 per share, and cash in lieu of any fractional shares. The Company issued 106,426,721 shares of Class A Common Stock to Mobile Mini stockholders as consideration for the Merger. The trading price of the Class A Common Stock was $12.53 per share on the closing date. In addition, Mobile Mini stock options converted into WillScot Mobile Mini stock options. The purchase price has been determined to be as follows: (in thousands, except share and per share data) Mobile Mini Common Stock outstanding 44,252,275 Share conversion ratio 2.405 Common Stock issued 106,426,721 Common Stock per share price as of July 1, 2020 $ 12.53 Fair value of shares of WillScot Class A Common Stock issued $ 1,333,527 Cash paid for fractional shares 30 Fair value of Mobile Mini Options converted to WillScot Mobile Mini Options 19,279 Total purchase price $ 1,352,836 The Merger was accounted for using the acquisition method of accounting, and WillScot is considered the accounting acquirer. Under the acquisition method of accounting, the Company is required to assign the purchase price to tangible and identifiable intangible assets acquired and liabilities assumed based on their fair values at the closing date. The excess of the purchase price over those fair values is recorded as goodwill. The Company's acquisition of Mobile Mini represents a non-cash investing outflow activity of $1,352,836 and the related issuance of equity including stock options represents a non-cash financing inflow activity of $1,352,836. The purchase price for the Merger was assigned to the underlying assets acquired and liabilities assumed based upon their fair values at the date of acquisition, July 1, 2020. The Company recorded the fair values based on independent valuations, discounted cash flow analyses, quoted market prices, contributory asset charges, and estimates made by management. The following table summarizes the July 1, 2020 preliminary fair values of the assets acquired and liabilities assumed. The final assignment of the fair value of the Merger, including the final valuation of acquired rental equipment, intangible assets, and the related deferred tax liabilities and the final assignment of goodwill to reporting units, was not complete as of December 31, 2020, but will be finalized within the allowable one-year measurement period. Opening Balance Sheet (in thousands) Current Balance Cash and cash equivalents $ 17,203 Trade receivables 87,492 (a) Inventories 8,987 Prepaid expenses and other current assets 13,264 Rental equipment 1,033,190 (b) Property, plant and equipment, net 161,401 (c) Operating lease assets 92,054 Intangible assets 382,500 (b) Goodwill identified 928,974 (d) Other non-current assets 2,387 Total identifiable assets acquired 2,727,452 Accounts payable (29,797) Accrued liabilities and interest (38,759) Deferred revenue and customer deposits (38,846) Operating lease liabilities (89,968) Debt and finance lease liabilities (897,244) Deferred tax liabilities (278,727) (e) Other long-term liabilities (1,275) Total liabilities assumed (1,374,616) Net assets acquired (purchase price) $ 1,352,836 (a) As of the acquisition date, the fair value of accounts receivable was $87.5 million, and the gross contractual amount was $99.8 million. The Company analyzed information available at the time of acquisition in estimating uncollectible receivables and the fair value of remaining receivables. The Company's analysis, as of the acquisition date, included an assessment of the risk of collectability of receivables by analyzing historical payment trends, the status of collection efforts, and any other pertinent customer specific information that existed as of the acquisition date. (b) The initial fair value assumptions used included preliminary estimates of the replacement cost of rental equipment, discount rates, royalty rates, and customer attrition rates which have been updated in preparing these valuations and the underlying assets have been adjusted from those previously recorded accordingly. Rental equipment and intangible assets were reduced by approximately $109.8 million and $183.1 million from amounts previously reported, respectively. (c) The initial fair value assumptions have been updated in preparing these valuations and the underlying assets have been adjusted from those previously recorded accordingly. Property, plant and equipment, net increased by approximately $8.2 million. (d) The goodwill is reflective of Mobile Mini’s going concern value and operational synergies that the Company expects to achieve that would not be available to other market participants. Goodwill from the Mobile Mini acquisition is not deductible for income tax purposes. (e) The deferred tax liability is reflective of a deferred tax asset valuation reversal, partially offset by a permanent difference for transaction costs. The change from the preliminary balance of deferred tax liabilities to the current balance was driven by the updates to the preliminary estimates of the replacement cost of rental equipment, discount rates, royalty rates, and customer attrition rates discussed in (b) above. Deferred tax liabilities decreased approximately $68 million from amounts previously reported. Mobile Mini has generated $316.5 million of revenue and $23.1 million of pre-tax income since the acquisition date, which is included in the consolidated statement of operations for the year ended December 31, 2020. Pro Forma Information The below pro forma results give effect to the following as if they occurred on January 1, 2019, (i) the Merger, (ii) borrowings under the Company's 2025 Secured Notes and 2020 ABL Facility (terms as defined in Note 11) used to repay certain debt in connection with the Merger, (iii) extinguishment of the Mobile Mini revolving credit facility and senior notes assumed in the Merger and immediately repaid, (iv) extinguishment of WillScot's 2017 ABL Facility and WillScot's 2022 Secured Notes (both as defined in Note 11) repaid in connection with the Merger and (v) elimination of WillScot's non-controlling interest and WillScot's Class B Common Stock in connection with the Merger. The pro forma information is not necessarily indicative of the Company’s results of operations had the Merger been completed on January 1, 2019, nor is it necessarily indicative of the Company’s future results. The pro forma information does not reflect any cost savings from operating efficiencies, synergies, or revenue opportunities that could result from the Merger. The tables below present unaudited pro forma combined statements of operations information for the years ended December 31, 2020 and 2019: (unaudited, in thousands) Year Ended December 31, 2020 Year Ended December 31, 2019 WillScot revenues $ 1,367,645 $ 1,063,665 Mobile Mini revenues 284,240 620,018 Pro forma revenues $ 1,651,885 $ 1,683,683 WillScot Mobile Mini pretax income (loss) $ 20,428 $ (13,734) (a) Mobile Mini pretax income 37,875 111,705 Pro forma pretax income 58,303 97,971 Pro forma adjustments to combined pretax income: Elimination of Merger transaction costs 80,852 — (b) Impact of fair value mark-ups on rental fleet depreciation (2,334) (4,667) (c) Other depreciation expense and intangible asset amortization (11,397) (22,399) (d) Interest expense (6,113) (1,916) (e) Elimination of Mobile Mini interest 15,921 39,672 (f) Elimination of loss on extinguishment of debt 19,682 1,512 (g) Pro forma pretax income 154,914 110,173 Income tax expense (34,549) (28,892) (h) Pro forma net income $ 120,365 $ 81,281 (a) Excludes impact of non-controlling interest which was eliminated as part of the Sapphire Exchange. See Note 12. (b) Eliminates discrete Merger transaction costs incurred as a result of the Mobile Mini Merger. (c) Depreciation on rental equipment and property, plant and equipment were adjusted for the preliminary determination of the fair value of equipment acquired in the Mobile Mini Merger. (d) Represents the differential in other depreciation and amortization expense related to the provisional fair value purchase accounting adjustments as a result of the Merger, principally the amortization of the Mobile Mini customer relationship estimated at $263 million over 13 years. (e) In connection with the Merger, the Company entered into a new ABL Facility and drew $1.47 billion at close with an estimated interest rate of 2.046%, issued the 2025 Secured Notes at 6.125%, repaid the 2022 Secured Notes and repaid the 2017 ABL Facility. Interest and amortization of deferred financing fees for the 2020 ABL Facility and the 2025 Secured Notes has been included offset by the removal of interest and amortization of deferred financing fees attributable to the 2022 Secured Notes and the 2017 ABL Facility. See Note11 for definitions of terms. (f) Interest and amortization of deferred financing fees on the senior notes and line of credit maintained by Mobile Mini which were assumed at acquisition and repaid immediately using proceeds from the 2020 ABL Facility and 2025 Secured Notes was eliminated. See Note 11 for definition of terms. (g) Elimination of loss on extinguishment of debt in connection with the redemption premium on the 2022 Secured Notes and unamortized deferred financing costs on the 2022 Secured Notes and 2017 ABL Facility. See Note11 for definitions of terms. (h) Reflects the recorded income tax provision plus the adjustment to recognize the income tax impacts of the unaudited pro forma adjustments for which a tax expense is recognized using a US federal and state statutory tax rate of 25.5%. This rate may vary from the effective tax rates of the historical and combined businesses. In addition, eliminates the 2020 reversal of $54.6 million of valuation allowance as a result of reassessment of the realizability of deferred tax assets as a result of the Merger. See Note 13.

Revenue (Tables)

Revenue (Tables)	12 Months Ended
	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The Company had total revenue in the following geographic areas for the years ended December 31, as follows: Year Ended December 31, (in thousands) 2020 2019 2018 US $ 1,227,465 $ 966,766 $ 685,350 Canada 79,630 80,514 50,144 Mexico 14,190 16,385 15,918 UK 46,360 — — Total revenues $ 1,367,645 $ 1,063,665 $ 751,412 The Company’s revenue by major product and service line for the years ended December 31, was as follows: Year Ended December 31, (in thousands) 2020 2019 2018 Modular space leasing revenue $ 596,880 $ 516,299 $ 360,240 Portable storage leasing revenue 125,216 24,277 21,682 Tank and pump leasing revenue 29,798 — — VAPS and third party leasing revenues (a) 202,938 159,327 104,870 Other leasing-related revenue (b) 46,615 44,282 31,443 Leasing revenue 1,001,447 744,185 518,235 Delivery and installation revenue 274,156 220,057 154,557 Total leasing and services revenue 1,275,603 964,242 672,792 New unit sales revenue 53,093 59,085 53,603 Rental unit sales revenue 38,949 40,338 25,017 Total revenues $ 1,367,645 $ 1,063,665 $ 751,412 (a) Includes $18.8 million , $15.9 million, and $10.8 million of VAPS service revenue for the years ended December 31, 2020, 2019 and 2018, respectively. (b) Includes primarily damage billings, delinquent payment charges, and other processing fees.
Future Commited Modular Leasing Revenues	Future committed leasing revenues under non-cancelable operating leases with the Company’s customers at December 31, 2020 for the years ended December 31, 2021 - 2025 and thereafter were as follows: (in thousands) Operating Leases 2021 $ 232,730 2022 75,664 2023 29,419 2024 11,643 2025 4,284 Thereafter 2,738 Total $ 356,478

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Lessee, Operating Lease, Liability, Maturity	As of December 31, 2020, the undiscounted future lease payments for operating and finance lease liabilities were as follows (in thousands): Operating Finance 2021 $ 60,120 $ 18,252 2022 51,184 17,158 2023 41,074 13,707 2024 33,336 10,786 2025 26,542 10,893 Thereafter 67,421 13,410 Total lease payments 279,677 84,206 Less: interest (47,853) (6,332) Present value of lease liabilities $ 231,824 $ 77,874 As of December 31, 2019, the undiscounted future lease payments for operating and finance lease liabilities were as follows (in thousands): Operating Finance 2020 $ 37,648 $ — 2021 33,903 — 2022 27,769 — 2023 21,926 — 2024 16,685 — Thereafter 47,916 — Total lease payments 185,847 — Less: interest (38,285) — Present value of lease liabilities $ 147,562 $ —
Finance Lease, Liability, Fiscal Year Maturity	As of December 31, 2020, the undiscounted future lease payments for operating and finance lease liabilities were as follows (in thousands): Operating Finance 2021 $ 60,120 $ 18,252 2022 51,184 17,158 2023 41,074 13,707 2024 33,336 10,786 2025 26,542 10,893 Thereafter 67,421 13,410 Total lease payments 279,677 84,206 Less: interest (47,853) (6,332) Present value of lease liabilities $ 231,824 $ 77,874 As of December 31, 2019, the undiscounted future lease payments for operating and finance lease liabilities were as follows (in thousands): Operating Finance 2020 $ 37,648 $ — 2021 33,903 — 2022 27,769 — 2023 21,926 — 2024 16,685 — Thereafter 47,916 — Total lease payments 185,847 — Less: interest (38,285) — Present value of lease liabilities $ 147,562 $ —
Lease Activity	The Company’s lease activity during the years ended December 31, 2020 and 2019 was as follows: Year Ended December 31, Financial Statement Line (in thousands) 2020 2019 Finance Lease Expense Amortization of finance lease assets $ 9,556 $ — Interest on obligations under finance leases 1,081 — Total finance lease expense $ 10,637 $ — Operating Lease Expense Fixed lease expense Cost of leasing and services $ 5,723 $ 6,737 Selling, general and administrative 43,482 34,058 Lease impairment expense and other related charges 2,800 2,611 Short-term lease expense Cost of leasing and services 25,576 29,729 Selling, general and administrative 2,067 2,071 Lease impairment expense and other related charges 471 — Variable lease expense Cost of leasing and services 6,981 3,787 Selling, general and administrative 5,436 4,231 Lease impairment expense and other related charges 855 — Total operating lease expense $ 93,391 $ 83,224
Weighted-Average Remaining Operating Lease Term and Weighted Average Discount Rate	Weighted-average remaining operating lease terms and the weighted average discount rates as of December 31, 2020 and 2019 were as follows: Lease Terms and Discount Rates December 31, 2020 December 31, 2019 Weighted-average remaining lease term - operating leases 6.4 years 6.5 years Weighted-average discount rate - operating leases 5.7 % 7.0 % Weighted-average remaining lease term - finance leases 4.6 years — Weighted-average discount rate - finance leases 2.9 % —

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2020
Inventory Disclosure [Abstract]
Schedule of Inventories	Inv entories at December 31, consisted of the following: (in thousands) 2020 2019 Raw materials $ 19,560 $ 15,387 Finished units 2,095 — Inventories $ 21,655 $ 15,387

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets at December 31 co nsisted of the following: (in thousands) 2020 2019 Tax receivables $ 4,618 $ 1,211 Prepaid insurance 5,859 2,099 Other prepaid expenses 19,477 11,311 Total prepaid expenses and other current assets $ 29,954 $ 14,621

Rental Equipment, Net (Tables)

Rental Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Schedule of Rental Equipment, Net	Depreciation is generally computed using the straight-line method over estimated useful lives, as follows: Estimated Useful Life Residual Value Modular space units 10 - 20 years 20 - 50% Portable storage units 30 years 55% Tank and pump equipment 7 - 25 years —% VAPS and other related rental equipment 1 - 8 years —% Depreciation is generally computed using the straight-line method over estimated useful lives as follows: Estimated Useful Life Buildings and leasehold improvements 10 - 40 years (a) Vehicles, machinery, and equipment 3 - 30 years Furniture and fixtures 3 - 10 years Software 3 - 10 years (a) Improvements to leased properties are depreciated over the lesser of the estimated useful life of the asset or the remaining term of the respective lease. Rental equipment, net at December 31 consisted of the following: (in thousands) 2020 2019 Modular space units $ 2,520,704 $ 2,372,069 Portable storage units 931,363 83,402 Tank and pump products 132,071 — Value added products 143,652 121,855 Total rental equipment 3,727,790 2,577,326 Less: accumulated depreciation (794,068) (632,890) Rental equipment, net $ 2,933,722 $ 1,944,436 Property, plant and equipment, net at December 31 consisted of the following: (in thousands) 2020 2019 Land, buildings, and leasehold improvements $ 154,210 $ 139,861 Vehicles, machinery, and office equipment 227,009 62,169 Software and other 20,800 27,342 Total property, plant and equipment 402,019 229,372 Less: accumulated depreciation (98,369) (81,683) Property, plant and equipment, net $ 303,650 $ 147,689

Property, Plant and Equipment_2

Property, Plant and Equipment, net (Tables)	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	Depreciation is generally computed using the straight-line method over estimated useful lives, as follows: Estimated Useful Life Residual Value Modular space units 10 - 20 years 20 - 50% Portable storage units 30 years 55% Tank and pump equipment 7 - 25 years —% VAPS and other related rental equipment 1 - 8 years —% Depreciation is generally computed using the straight-line method over estimated useful lives as follows: Estimated Useful Life Buildings and leasehold improvements 10 - 40 years (a) Vehicles, machinery, and equipment 3 - 30 years Furniture and fixtures 3 - 10 years Software 3 - 10 years (a) Improvements to leased properties are depreciated over the lesser of the estimated useful life of the asset or the remaining term of the respective lease. Rental equipment, net at December 31 consisted of the following: (in thousands) 2020 2019 Modular space units $ 2,520,704 $ 2,372,069 Portable storage units 931,363 83,402 Tank and pump products 132,071 — Value added products 143,652 121,855 Total rental equipment 3,727,790 2,577,326 Less: accumulated depreciation (794,068) (632,890) Rental equipment, net $ 2,933,722 $ 1,944,436 Property, plant and equipment, net at December 31 consisted of the following: (in thousands) 2020 2019 Land, buildings, and leasehold improvements $ 154,210 $ 139,861 Vehicles, machinery, and office equipment 227,009 62,169 Software and other 20,800 27,342 Total property, plant and equipment 402,019 229,372 Less: accumulated depreciation (98,369) (81,683) Property, plant and equipment, net $ 303,650 $ 147,689

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of goodwill activity	Changes in the carrying amount of goodwill were as follows: (in thousands) Balance at December 31, 2018 $ 247,017 Changes to purchase price accounting - Modspace (13,479) Effects of movements in foreign exchange rates 1,639 Balance at December 31, 2019 235,177 Acquisition of Mobile Mini 928,974 Effects of movements in foreign exchange rates 7,068 Balance at December 31, 2020 $ 1,171,219
Schedule of finite lived intangible assets	Intangible assets other than goodwill at December 31, consisted of the following: December 31, 2020 (in thousands) Weighted average remaining life (in years) Gross carrying amount Accumulated amortization Net book value Intangible assets subject to amortization: Trade name - ModSpace 0.7 $ 3,000 $ (2,375) $ 625 Mobile Mini customer relationships 8.0 217,000 (12,053) 204,947 Technology 5.5 1,500 (125) 1,375 Indefinite-lived intangible assets: Trade name - Mobile Mini 164,000 — 164,000 Trade name - WillScot 125,000 — 125,000 Total intangible assets other than goodwill $ 510,500 $ (14,553) $ 495,947 December 31, 2019 (in thousands) Weighted average remaining life (in years) Gross carrying amount Accumulated amortization Net book value Intangible assets subject to amortization: Trade name - ModSpace 1.7 $ 3,000 $ (1,375) $ 1,625 Total intangible assets subject to amortization 3,000 (1,375) 1,625 Indefinite-lived intangible assets: Trade name - WillScot 125,000 — 125,000 Total intangible assets other than goodwill $ 128,000 $ (1,375) $ 126,625
Schedule of indefinite lived intangible assets	Intangible assets other than goodwill at December 31, consisted of the following: December 31, 2020 (in thousands) Weighted average remaining life (in years) Gross carrying amount Accumulated amortization Net book value Intangible assets subject to amortization: Trade name - ModSpace 0.7 $ 3,000 $ (2,375) $ 625 Mobile Mini customer relationships 8.0 217,000 (12,053) 204,947 Technology 5.5 1,500 (125) 1,375 Indefinite-lived intangible assets: Trade name - Mobile Mini 164,000 — 164,000 Trade name - WillScot 125,000 — 125,000 Total intangible assets other than goodwill $ 510,500 $ (14,553) $ 495,947 December 31, 2019 (in thousands) Weighted average remaining life (in years) Gross carrying amount Accumulated amortization Net book value Intangible assets subject to amortization: Trade name - ModSpace 1.7 $ 3,000 $ (1,375) $ 1,625 Total intangible assets subject to amortization 3,000 (1,375) 1,625 Indefinite-lived intangible assets: Trade name - WillScot 125,000 — 125,000 Total intangible assets other than goodwill $ 128,000 $ (1,375) $ 126,625
Finite-lived Intangible Assets Amortization Expense	As of December 31, 2020, the expected future amortization expense for intangible assets is as follows: (in thousands) Amortization Expense 2021 $ 27,167 2022 26,542 2023 26,542 2024 26,542 2025 26,542 Thereafter 73,612 Total $ 206,947

Deferred Revenue and Customer_2

Deferred Revenue and Customer Deposits (Tables)	12 Months Ended
	Dec. 31, 2020
Other Liabilities Disclosure [Abstract]
Schedule of Deferred Revenue and Customer Deposits	Deferred revenue and customer deposits at December 31 consist ed of the following: (in thousands) 2020 2019 Current: Deferred revenue $ 133,156 $ 81,303 Customer deposits 2,329 1,675 Total current deferred revenue and customer deposits $ 135,485 $ 82,978 Long-term: Deferred revenue $ 12,060 $ 12,342 Total long-term deferred revenue and customer deposits $ 12,060 $ 12,342

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Schedule of Debt	The carrying value of debt outstanding at December 31 consisted of the following: (in thousands, except rates) Interest rate Year of maturity 2020 2019 2022 Secured Notes 7.875% 2022 $ — $ 264,576 2023 Secured Notes 6.875% 2023 — 482,768 2025 Secured Notes 6.125% 2025 637,068 — ABL Facility (a) Varies 2025 1,263,833 885,245 2028 Secured Notes 4.625% 2028 491,555 — Finance Leases Varies Varies 77,874 — Total debt 2,470,330 1,632,589 Less: current portion of long-term debt 16,521 — Total long-term debt $ 2,453,809 $ 1,632,589 (a) As of December 31, 2020, the Company had no outstanding principal borrowings on the Multicurrency Facility and $7.9 million of related debt issuance costs. No related debt issuance costs were recor ded as a direct offset against the principal borrowings on the Multicurrency Facility, and the $7.9 million in excess of principal was included in other non-current assets on the consolidated balance sheet. As of December 31, 2019, the Company had no outstanding principal borrowings on the 2017 Canadian ABL Facility and $2.1 million of related debt issuance costs. No related debt issuance costs were recorded as a direct offset against the principal of the 2017 Canadian ABL Facility, and the $2.1 million in excess of principal was included in other non-current assets on the consolidated balance sheet.
Schedule of Maturities of Debt and Lease Obligation	Maturities of long-term debt, including finance leases, during the years subsequent to December 31, 2020 are as follows: (in thousands) 2021 $ 18,252 2022 $ 17,158 2023 $ 13,707 2024 $ 10,786 2025 $ 1,965,505 Thereafter $ 513,410
Schedule of Amortization of Deferred Debt Issuance Costs	These debt costs will be amortized and included as part of interest expense over the remaining contractual terms of those debt instruments for each of the next five years as follows: (in thousands) Debt issuance cost amortization 2021 $ 14,317 2022 $ 14,540 2023 $ 14,778 2024 $ 15,031 2025 $ 8,050 Thereafter $ 3,365
Debt Redemption	On and after June 15, 2022, the Company may redeem the 2025 Secured Notes, in whole or in part, at the redemption prices expressed as percentages of principal amount set forth below plus accrued and unpaid interest to but not including the applicable redemption date, subject to the holders' right to receive interest due on an interest payment date falling on or prior to the redemption date, if redeemed during the twelve-month period beginning on June 15 of each of the years set forth below. Year Redemption Price 2022 103.063 % 2023 101.531 % 2024 and thereafter 100.000 % The 2025 Secured Notes are unconditionally guaranteed by each of WSII's direct and indirect domestic subsidiaries and WSII's parent, Holdings (collectively, "the Note Guarantors"). WillScot Mobile Mini is not a guarantor of the 2025 Secured Notes. The Note Guarantors, as well as certain of the Company’s non-US subsidiaries, are guarantors or borrowers under the 2020 ABL Facility. To the extent lenders under the 2020 ABL Facility release the guarantee of any Note Guarantor, such Note Guarantor will also be released from obligations under the 2025 Secured Notes. These guarantees are secured by a second priority security interest in substantially all of the assets of WSII and the Note Guarantors, subject to customary exclusions. The guarantees of the 2025 Secured Notes by WillScot Equipment II, LLC, a Delaware limited liability company which holds certain of WSII’s assets in the US, will be subordinated to its obligations under the 2020 ABL Facility. On and after August 15, 2023, the Company may redeem the 2028 Secured Notes, in whole or in part, at the redemption prices expressed as percentages of principal amount set forth below plus accrued and unpaid interest to but not including the applicable redemption date, subject to the holders' right to receive interest due on an interest payment date falling on or prior to the redemption date, if redeemed during the twelve-month period beginning on August 15 of each of the years set forth below. Year Redemption Price 2023 102.313 % 2024 101.156 % 2025 and thereafter 100.000 %

Equity (Tables)

Equity (Tables)	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Loss	The changes in accumulated other comprehensive loss ("AOCI"), net of tax, for the years ended December 31, 2020, 2019 and 2018, were as follows: (in thousands) Foreign Currency Translation Unrealized losses on hedging activities Total Balance at December 31, 2017 $ (49,497) $ — $ (49,497) Other comprehensive loss before reclassifications (11,639) (6,240) (17,879) Reclassifications from AOCI to income (a) — 285 285 Reclassifications from AOCI to retained earnings (b) (2,540) — (2,540) Less other comprehensive income attributable to non-controlling interest 1,068 537 1,605 Balance at December 31, 2018 (62,608) (5,418) (68,026) Other comprehensive income (loss) before reclassifications 10,586 (7,930) 2,656 Reclassifications from AOCI to income (a) — 3,121 3,121 Less other comprehensive income (loss) attributable to non-controlling interest (960) 434 (526) Balance at December 31, 2019 (52,982) (9,793) (62,775) Other comprehensive income (loss) before reclassifications 28,404 (11,874) 16,530 Reclassifications from AOCI to income (a) — 10,125 10,125 Less other comprehensive income attributable to non-controlling interest 1,183 702 1,885 Impact of elimination of non-controlling interest on accumulated other comprehensive income (1,299) (1,673) (2,972) Balance at December 31, 2020 $ (24,694) $ (12,513) $ (37,207)

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Benefit (Expense)	The components of income tax (benefit) expense for the years ended December 31, 2020 , 2019 and 2018 are comprised of the following: (in thousands) 2020 2019 2018 US Federal and State Current $ 1,601 $ 827 $ 668 Deferred (58,026) 1,904 (36,149) Outside of US Current 2,104 (395) 924 Deferred 2,870 (4,527) (4,043) Total income tax benefit $ (51,451) $ (2,191) $ (38,600)
Schedule of Effective Income Tax Rate Reconciliation	Income tax results differed from the amount computed by applying the US statutory income tax rate of 21% to the income (loss) before income taxes for the following reasons for the years ended December 31, 2020 , 2019 and 2018: (in thousands) 2020 2019 2018 Income (loss) before income tax US $ 3,136 $ (9,477) $ (80,824) Non-US 17,292 (4,257) (11,348) Total income (loss) before income tax $ 20,428 $ (13,734) $ (92,172) US Federal statutory income tax expense (benefit) $ 4,290 $ (2,884) $ (19,356) Effect of tax rates in foreign jurisdictions 128 (207) (626) State income tax expense (benefit), net of federal benefit 3,962 1,829 (2,478) Unremitted foreign earnings — — (6,793) Valuation allowances (56,479) 961 (11,871) Non-deductible items 187 (233) — Non-deductible executive compensation 1,449 490 — Non-deductible transaction costs 4,425 (12) 1,134 Uncertain tax positions (11,166) — — Tax law changes (excluding valuation allowance) (a) 2,523 (2,785) 64 Other (770) 650 1,326 Reported income tax benefit $ (51,451) $ (2,191) $ (38,600) Effective income tax rate (251.87) % 15.95 % 41.88 % (a) Tax law changes include the following amounts: 2020 and 2019 primarily represents changes in tax law in non-US jurisdictions and 2018 primarily represents US tax reform items.
Schedule of Deferred Income Taxes	Significant components of the Company’s deferred tax assets and liabilities are as follows: (in thousands) 2020 2019 Deferred tax assets Deferred interest expense $ 128,346 $ 138,206 Employee benefit plans 3,532 1,916 Accrued liabilities 10,692 8,494 Deferred revenue 32,412 20,951 Operating lease liability 58,044 37,438 Other 13,628 7,817 Tax loss carryforwards 295,326 231,503 Deferred tax assets, gross 541,980 446,325 Valuation allowance (25,158) (80,241) Net deferred income tax asset $ 516,822 $ 366,084 Deferred tax liabilities Rental equipment and other property, plant and equipment $ (648,966) $ (375,682) Intangible assets (117,403) (23,690) ROU asset (57,820) (37,218) Deferred tax liability (824,189) (436,590) Net deferred income tax liability $ (307,367) $ (70,506)
Summary of Tax Loss Carryforwards	The Company’s tax loss carryforwards are as follows at December 31, 2020: (in thousands) Loss Expiration Jurisdiction: US - Federal $ 1,187,500 2022 – 2037, Indefinite US - State 700,500 2021 –2040, Indefinite Foreign - Mexico & Canada 14,100 2025 – 2038 Total $ 1,902,100
Schedule of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: (in thousands) 2020 2019 2018 Unrecognized tax benefits – January 1, $ 63,747 $ 64,444 $ 72,660 Increases based on tax positions related to current period 1,211 — 1,545 Increases based on tax positions related to prior period — 268 — Decreases based on tax positions related to prior period — (287) (9,016) Decrease from expiration of statute of limitations (10,464) (678) (745) Unrecognized tax benefits – December 31, $ 54,494 $ 63,747 $ 64,444

Derivatives (Tables)

Derivatives (Tables)	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Interest Rate Agreements	The location and the fair value of derivative instruments designated as hedges in the consolidated balance sheets as of December 31 was as follows: (in thousands) Balance Sheet Location 2020 2019 Cash Flow Hedges: Interest rate swap Accrued liabilities $ 11,619 $ 5,348 Interest rate swap Other non-current liabilities $ 5,308 $ 8,943
Schedule of Impact of Interest Rate Swap on Other Comprehensive Income, AOCI, and Statement of Operations	The following table discloses the impact of the interest rate swap, excluding the impact of income taxes, on other comprehensive income (“OCI”), AOCI and the Company’s statement of operations for the years ended December 31: (in thousands) 2020 2019 2018 Loss recognized in OCI $ (2,288) $ (6,280) $ (7,777) Location of loss recognized in income Interest expense Interest expense Interest expense Loss reclassified from AOCI into income (effective portion) $ (10,125) $ (3,254) $ (373)

Fair Value Measures (Tables)

Fair Value Measures (Tables)	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Carrying Amounts and Fair Values of Financial Assets and Liabilities	The following table shows the carrying amounts and fair values of financial assets and liabilities, including their levels in the fair value hierarchy: December 31, 2020 December 31, 2019 Carrying Amount Fair Value Carrying Amount Fair Value (in thousands) Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 US ABL Facilities (a) $ 1,263,833 $ — $ 1,304,612 $ — $ 885,245 $ — $ 903,000 $ — Multicurrency Facility (a) — $ — — — — — — — 2022 Secured Notes (a) — — — — 264,576 — 282,250 — 2023 Secured Notes (a) — — — — 482,768 — 517,334 — 2025 Secured Notes (a) 637,068 — 694,876 — — — — — 2028 Secured Notes (a) 491,555 — 518,820 — — — — — Total $ 2,392,456 $ — $ 2,518,308 $ — $ 1,632,589 $ — $ 1,702,584 $ — (a) The carrying values of the US ABL Facilities, the Multicurrency Facility, the 2025 Secured Notes, and the 2028 Secured Notes included $40.8 million, $0, $12.9 million, and $8.4 million of unamortized debt issuance costs as of December 31, 2020, which were presented as a direct reduction of the corresponding liability. The carrying values of the US ABL Facility, the Canadian ABL Facility, the 2022 Secured Notes, and the 2023 Secured Notes inclu ded $17.8 million, $0, $5.4 million, and $7.2 million

Restructuring (Tables)

Restructuring (Tables)	12 Months Ended
	Dec. 31, 2020
Restructuring and Related Activities [Abstract]
Summary of Activities in the Restructuring Accruals	The following is a summary of the activity in the Company’s restructuring accruals for years ended December 31: (in thousands) Year Ended December 31, 2020 2019 2018 Employee Costs Facility Exit Costs Total Employee Costs Facility Exit Costs Total Employee Costs Facility Exit Costs Total Beginning balance $ 447 $ — $ 447 $ 4,544 $ 972 $ 5,516 $ 227 $ — $ 227 Reclassification of liability to operating lease asset at the adoption of ASC 842 (a) — — — — (972) (972) — — — Charges 6,510 17 6,527 1,955 1,800 3,755 10,182 5,286 15,468 Cash payments (5,356) — (5,356) (5,694) — (5,694) (5,806) (4,314) (10,120) Foreign currency translation 30 — 30 (136) — (136) (59) — (59) Non-cash movements 119 (17) 102 (222) (1,800) (2,022) — — — Ending balance $ 1,750 $ — $ 1,750 $ 447 $ — $ 447 $ 4,544 $ 972 $ 5,516 (a) As a result of the adoption of ASC 842, the January 1, 2019 restructuring liability attributable to “cease-use” locations was reclassified to operating lease assets and 2019 costs related to the termination of leases for duplicative branches and corporate facilities are now recorded in lease impairment charges and other related costs.

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Restricted Stock Awards	The following table summarizes the Company's RSA activity during the years ended December 31, 2020, 2019 and 2018 : Number of Shares Weighted-Average Grant Date Fair Value Balance, December 31, 2017 — $ — Granted 72,053 $ 15.57 Balance, December 31, 2018 72,053 $ 15.57 Granted 52,755 $ 14.69 Vested (72,053) $ 15.57 Balance, December 31, 2019 52,755 $ 14.69 Granted 65,959 $ 11.75 Vested (61,266) $ 14.28 Balance, December 31, 2020 57,448 $ 11.75
Restricted Stock Units	The following table summarizes the Company's Time-Based RSU activity during the years ended December 31, 2020, 2019 and 2018 : Number of Shares Weighted-Average Grant Date Fair Value Balance, December 31, 2017 — $ — Granted 921,730 $ 13.60 Forfeited (68,997) $ 13.60 Balance, December 31, 2018 852,733 $ 13.60 Granted 478,400 $ 11.69 Forfeited (52,648) $ 12.78 Vested (213,180) $ 12.78 Balance, December 31, 2019 1,065,305 $ 12.78 Granted 632,864 $ 14.37 Forfeited (33,558) $ 13.28 Vested (538,845) $ 13.24 Balance, December 31, 2020 1,125,766 $ 13.44 The following table summarizes the Company's Performance-Based RSU award activity during the years ended December 31, 2020 and 2019 : Number of Shares Weighted-Average Grant Date Fair Value Balance, December 31, 2018 — $ — Granted 302,182 $ 13.22 Forfeited (13,901) $ 13.22 Balance, December 31, 2019 288,281 $ 13.22 Granted 325,256 $ 16.35 Forfeited (12,700) $ 14.70 Vested (7,449) $ 16.82 Balance, December 31, 2020 593,388 $ 14.88
Stock Option Awards	The following table summarizes the Company's stock option activity during the years ended December 31, 2020, 2019 and 2018 : WillScot Options Weighted-Average Exercise Price per Share Converted Weighted-Average Exercise Price per Share Outstanding options, December 31, 2017 — $ — — $ — Granted 589,257 $ 13.60 — $ — Outstanding options, December 31, 2018 589,257 $ 13.60 — $ — Forfeited (41,302) $ 13.60 — $ — Exercised (13,767) $ 13.60 — $ — Outstanding options, December 31, 2019 534,188 $ 13.60 — $ — Converted at Merger — $ — 7,361,516 $ 13.52 Exercised — $ — (428,653) $ 13.07 Cancelled in settlement, net of taxes — $ — (4,901,408) $ 13.04 Outstanding options, December 31, 2020 534,188 $ 13.60 2,031,455 $ 14.78 Fully vested and exercisable options, December 31, 2018 — $ — — $ — Vested during 2019 133,547 $ 13.60 — $ — Fully vested and exercisable options, December 31, 2019 133,547 $ 13.60 — $ — Vested during 2020 133,547 $ 13.60 2,031,455 $ 14.78 Fully vested and exercisable options, December 31, 2020 267,094 $ 13.60 2,031,455 $ 14.78

Segment Reporting (Tables)

Segment Reporting (Tables)	12 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	The following tables set forth certain information regarding each of the Company’s reportable segments fo r the years ended December 31, 2020, 2019, and 2018, respectively. Consistent with the financial statements, the segment results only include results from Mobile Mini's operations after July 1, 2020, the Merger date. Please refer to the Management Discussion and Analysis of Financial Condition and Results of Operations included in this document, for pro forma results inclusive of Mobile Mini's financial results for periods prior to the Merger date. Year Ended December 31, 2020 (in thousands) NA Modular NA Storage UK Storage Tank and Pump Unallocated Costs Total Revenues: Leasing and services revenue: Leasing $ 770,330 $ 166,128 $ 32,633 $ 32,356 $ 1,001,447 Delivery and installation 208,079 42,655 9,409 14,013 274,156 Sales revenue: New units 41,858 6,976 3,124 1,135 53,093 Rental units 30,895 6,070 1,195 789 38,949 Total revenues 1,051,162 221,829 46,361 48,293 1,367,645 Costs: Cost of leasing and services: Leasing 194,442 19,925 7,391 5,618 227,376 Delivery and installation 175,705 27,029 6,353 11,015 220,102 Cost of sales: New units 27,555 4,244 2,301 741 34,841 Rental units 19,213 4,261 1,026 272 24,772 Depreciation of rental equipment 182,605 9,585 1,648 6,743 200,581 Gross profit $ 451,642 $ 156,785 $ 27,642 $ 23,904 $ 659,973 Other selected data: Adjusted EBITDA $ 394,805 $ 99,837 $ 17,822 $ 17,843 $ — $ 530,307 Selling, general and administrative expense (a) $ 242,010 $ 66,533 $ 11,468 $ 12,804 $ 91,864 $ 424,679 Purchases of rental equipment and refurbishments $ 153,327 $ 14,969 $ 1,693 $ 2,394 $ — $ 172,383 (a) Includes both SG&A expense and Transaction costs from the consolidated statement of operations. Year Ended December 31, 2019 (in thousands) NA Modular NA Storage UK Storage Tank and Pump Unallocated Costs Total Revenues: Leasing and services revenue: Leasing $ 744,185 $ — $ — $ — $ 744,185 Delivery and installation 220,057 — — — 220,057 Sales revenue: New units 59,085 — — — 59,085 Rental units 40,338 — — — 40,338 Total Revenues 1,063,665 — — — 1,063,665 Costs: Cost of leasing and services: Leasing 213,151 — — — 213,151 Delivery and installation 194,107 — — — 194,107 Cost of sales: New units 42,160 — — — 42,160 Rental units 26,255 — — — 26,255 Depreciation of rental equipment 174,679 — — — 174,679 Gross profit $ 413,313 $ — $ — $ — $ 413,313 Other selected data: Adjusted EBITDA $ 356,548 $ — $ — $ — $ — $ 356,548 Selling, general and administrative expense $ 235,228 $ — $ — $ — $ 35,776 $ 271,004 Purchases of rental equipment and refurbishments $ 205,106 $ — $ — $ — $ — $ 205,106 Year Ended December 31, 2018 (in thousands) NA Modular NA Storage UK Storage Tank and Pump Unallocated Costs Total Revenues: Leasing and services revenue: Leasing $ 518,235 $ — $ — $ — $ 518,235 Delivery and installation 154,557 — — — 154,557 Sales revenue: New units 53,603 — — — 53,603 Rental units 25,017 — — — 25,017 Total revenues 751,412 — — — 751,412 Costs: Cost of leasing and services: Leasing 143,120 — — — 143,120 Delivery and installation 143,950 — — — 143,950 Cost of sales: New units 36,863 — — — 36,863 Rental units 16,659 — — — 16,659 Depreciation of rental equipment 121,436 — — — 121,436 Gross profit $ 289,384 $ — $ — $ — $ 289,384 Other selected data: Adjusted EBITDA $ 215,533 $ — $ — $ — $ — $ 215,533 Selling, general and administrative expense (a) $ 200,895 $ — $ — $ — $ 53,976 $ 254,871 Purchase of rental equipment and refurbishments $ 160,883 $ — $ — $ — $ — $ 160,883 (a) Includes both SG&A expense and Transaction costs from the consolidated statement of operati ons. The following tables present a reconciliation of the Company’s net income (loss) to Adjusted EBITDA for the years ended December 31, 2020, 2019, and 2018, respectively: Year Ended December 31, (in thousands) 2020 2019 2018 Net income (loss) attributable to WillScot Mobile Mini $ 70,666 $ (11,122) $ (51,175) Net income (loss) attributable to non-controlling interest, net of tax 1,213 (421) (4,532) Non-cash deemed dividend related to warrant exchange — — 2,135 Loss on extinguishment of debt 42,401 8,755 — Income tax benefit (51,451) (2,191) (38,600) Interest expense 119,886 122,504 98,433 Depreciation and amortization 243,830 187,074 134,740 Currency (gains) losses, net (355) (688) 2,454 Goodwill and other impairment charges — 2,848 1,600 Restructuring costs, lease impairment expense and other related charges 11,403 12,429 15,468 Transaction costs 64,053 — 20,051 Integration costs 18,338 26,607 30,006 Stock compensation expense 9,879 6,686 3,439 Other 444 4,067 1,514 Adjusted EBITDA $ 530,307 $ 356,548 $ 215,533
Reconciliation of Assets from Segment to Consolidated	Assets related to the Company’s reportable segments include the following: (in thousands) NA Modular NA Storage UK Storage Tank and Pump Total As of December 31, 2020: Goodwill $ 235,828 $ 726,529 $ 65,600 $ 143,262 $ 1,171,219 Intangible assets, net $ 125,625 $ 329,437 $ 11,177 $ 29,708 $ 495,947 Rental equipment, net $ 1,888,287 $ 772,356 $ 147,720 $ 125,359 $ 2,933,722 As of December 31, 2019: Goodwill $ 235,177 $ — $ — $ — $ 235,177 Intangible assets, net $ 126,625 $ — $ — $ — $ 126,625 Rental equipment, net $ 1,944,436 $ — $ — $ — $ 1,944,436

Related Parties (Tables)

Related Parties (Tables)	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Schedule of Related Parties	Related party balances included in the Company’s consolidated balance sheets at December 31, consisted of the following: (in thousands) Financial statement line Item 2020 2019 Receivables due from affiliates Trade receivables, net of allowances for credit losses $ 30 $ 26 Amounts due to affiliates Accrued liabilities (461) (236) Total related party liabilities, net $ (431) $ (210) Related party transactions included in the Company’s consolidated statements of operations for the years ended December 31, consisted of the following: (in thousands) Financial statement line item 2020 2019 2018 Leasing revenue from related parties Leasing revenue $ 1,066 $ 316 $ 720 Rental unit sales to related parties Rental unit sales 380 — 1,548 Consulting expense to related party (a) Selling, general & administrative expense (5,194) (1,029) (3,070) Total related party expense, net $ (3,748) $ (713) $ (802) (a) Two of the Company's directors also serve on the Board of Directors of a consulting firm from which the Company incurs professional fees.

Quarterly Financial Data (Table

Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data	The following tables present certain unaudited consolidated quarterly financial information for each of the eight quarters end ed December 31, 2020. In line with our filings with the SEC, prior to June 30, 2020, WillScot Mobile Mini refers to historical WillScot Corp. filed numbers. Post July 1, 2020, WillScot Mobile Mini refers to the combined company. (in thousands, except share and per share data) Quarter Ended (unaudited) 2020 March 31 June 30 September 30 December 31 Leasing and services revenue $ 239,422 $ 241,783 $ 384,776 $ 409,622 Total revenue $ 255,821 $ 256,862 $ 417,315 $ 437,647 Gross profit $ 106,190 $ 109,964 $ 209,564 $ 234,255 Operating income $ 25,373 $ 41,067 $ 25,012 $ 91,263 Net (loss) income $ (3,674) $ 12,833 $ 16,252 $ 46,468 Net (loss) income attributable to WillScot Mobile Mini $ (3,544) $ 11,490 $ 16,252 $ 46,468 (Loss) earnings per share - basic $ (0.03) $ 0.10 $ 0.07 $ 0.20 (Loss) earnings per share - diluted $ (0.03) $ 0.10 $ 0.07 $ 0.20 Weighted average shares - basic 109,656,646 110,692,426 226,649,993 228,637,826 Weighted average shares - diluted 109,656,646 111,432,963 231,216,573 236,696,853 (in thousands, except share and per share data) Quarter Ended (unaudited) 2019 March 31 June 30 September 30 December 31 Leasing and services revenue $ 227,292 $ 241,784 $ 249,411 $ 245,755 Total revenue $ 253,685 $ 263,713 $ 268,222 $ 278,045 Gross profit $ 103,331 $ 101,484 $ 99,307 $ 109,191 Operating income $ 21,464 $ 26,294 $ 29,781 $ 39,986 Net (loss) income $ (10,029) $ (11,438) $ 996 $ 8,928 Net (loss) income attributable to WillScot Mobile Mini $ (9,271) $ (10,606) $ 701 $ 8,054 (Loss) earnings per share - basic $ (0.09) $ (0.10) $ 0.01 $ 0.07 (Loss) earnings per share - diluted $ (0.09) $ (0.10) $ 0.01 $ 0.07 Weighted average shares - basic 108,523,269 108,693,924 108,720,857 108,793,847 Weighted average shares - diluted 108,523,269 108,693,924 112,043,866 114,080,059

Earnings (Loss) Per Share (Tabl

Earnings (Loss) Per Share (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Schedule of Weighted Average Number of Shares	The following table reconciles the weighted average shares outstanding for the basic calculation to the weighted average shares outstanding for the diluted calculation for year ended December 31, 2020: (in thousands) December 31, 2020 Weighted average Common Shares outstanding - basic 169,230 Dilutive effect of outstanding securities: Warrants 3,116 RSAs 33 Time-Based RSUs 315 Performance-Based and Market-Based RSUs 322 Stock Options 634 Weighted average Common Shares outstanding - dilutive 173,650

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Narrative (Details) $ / shares in Units, $ in Thousands	Jul. 01, 2020$ / shares	Dec. 31, 2020USD ($)$ / sharesshares	Dec. 31, 2019USD ($)$ / shares	Dec. 31, 2018USD ($)	Jan. 01, 2019USD ($)	Dec. 31, 2017USD ($)
Business Acquisition [Line Items]
Par value (in USD per share) | $ / shares	$ 0.0001	$ 0.0001
Capitalized implementation costs for cloud computing arrangements		$ 4,000
Matching contributions to defined contribution plans		$ 7,100	$ 5,400	$ 3,800
Shares authorized under plan (in shares) | shares		6,488,988
Billing period term		28 days
Advertising and promotion expense		$ 7,300	4,000	4,400
Debt		2,470,330	1,632,589
Deferred tax liabilities		307,541	70,693
Equity		2,141,277	708,955	$ 702,197		$ 484,550
Lease liability		231,824	147,562		$ 138,500
ROU assets		$ 232,094	$ 146,698		141,400
Class A Common Stock
Business Acquisition [Line Items]
Par value (in USD per share) | $ / shares	$ 0.0001		$ 0.0001
Mobile Mini, Inc.
Business Acquisition [Line Items]
Number of shares exchanged (in shares)	2.405
Mobile Mini, Inc.
Business Acquisition [Line Items]
Par value (in USD per share) | $ / shares	$ 0.01
Minimum
Business Acquisition [Line Items]
Operating lease term		1 month
Maximum
Business Acquisition [Line Items]
Operating lease term		60 months
Average
Business Acquisition [Line Items]
Operating lease term		9 months
Accounting Standards Update 2016-02
Business Acquisition [Line Items]
Property, plant and equipment, net					(31,000)
Debt					(37,900)
Deferred tax liabilities					1,800
Equity					$ 5,200
Largest Customer | Trade receivables, net of allowances for credit losses | Credit Concentration Risk
Business Acquisition [Line Items]
Concentration risk, percentage		1.20%	4.10%
Top Five Customers | Trade receivables, net of allowances for credit losses | Credit Concentration Risk
Business Acquisition [Line Items]
Concentration risk, percentage		4.90%	1.50%
RSAs
Business Acquisition [Line Items]
Vesting period		1 year
Time-Based RSUs
Business Acquisition [Line Items]
Vesting period		4 years
Performance-Based RSUs
Business Acquisition [Line Items]
Performance period		3 years
Minimum payout percentage		0.00%	0.00%
Maximum payout percentage		150.00%	150.00%
Target payout percentage		100.00%
Target performance threshold		50.00%
Minimum performance threshold		25.00%
Maximum performance threshold		75.00%
Stock Options
Business Acquisition [Line Items]
Vesting period		4 years
Expiration period		10 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Activity in Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of year	$ 15,828	$ 9,340	$ 4,845
Provision for credit losses, net of recoveries	31,386	14,496	7,656
Write-offs	(18,034)	(7,945)	(3,089)
Foreign currency translation and other	78	(63)	(72)
Balance at end of period	29,258	15,828	$ 9,340
Provision for credit losses recorded as a reduction to revenue for the provision of specific receivables whole collection is not considered probable	$ 18,000	$ 10,000

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Rental Equipment (Details)	12 Months Ended
	Dec. 31, 2020
Portable storage units
Property, Plant and Equipment [Line Items]
Estimated Useful Life	30 years
Residual Value	55000.00%
Tank and pump equipment
Property, Plant and Equipment [Line Items]
Residual Value	0.00%
VAPS and other related rental equipment
Property, Plant and Equipment [Line Items]
Residual Value	0.00%
Minimum | Modular space units
Property, Plant and Equipment [Line Items]
Estimated Useful Life	10 years
Residual Value	20000.00%
Minimum | Tank and pump equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Life	7 years
Minimum | VAPS and other related rental equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Life	1 year
Maximum | Modular space units
Property, Plant and Equipment [Line Items]
Estimated Useful Life	20 years
Residual Value	50.00%
Maximum | Tank and pump equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Life	25 years
Maximum | VAPS and other related rental equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Life	8 years

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Property, Plant and Equipment (Details)	12 Months Ended
	Dec. 31, 2020
Land Improvements
Property, Plant and Equipment [Line Items]
Estimated Useful Life	15 years
Buildings and leasehold improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	10 years
Buildings and leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	40 years
Vehicles, machinery, and equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Vehicles, machinery, and equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	30 years
Furniture and fixtures | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Furniture and fixtures | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	10 years
Software | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Software | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	10 years

Business Combinations and Acq_3

Business Combinations and Acquisition - Tyson Acquisitions, Additional Information (Details) $ in Millions	Jan. 03, 2018USD ($)
Tyson
Business Acquisition [Line Items]
Cash consideration	$ 24

Business Combinations and Acq_4

Business Combinations and Acquisitions - ModSpace Acquisition, Additional Information (Details) - USD ($)	Aug. 15, 2018	Jul. 30, 2018	Jun. 19, 2019	Aug. 03, 2018
Business Acquisition [Line Items]
Closing price (in dollars per share)	$ 15.78
ModSpace
Business Acquisition [Line Items]
Consideration	$ 1,200,000,000
Cash consideration	$ 1,100,000,000
Warrant exercise price (in USD per share)	$ 15.50
Working capital adjustment	$ 4,700,000
Fair market value of warrants (in dollars per share)	$ 5.23
Discount rate	6.00%
Common Stock | ModSpace
Business Acquisition [Line Items]
Purchase price paid in stock (in shares)	6,458,229
Purchase price paid in stock	$ 95,800,000
Fair value of stock consideration (in dollars per share)	$ 14.83
Warrants | ModSpace
Business Acquisition [Line Items]
Purchase price paid in stock (in shares)	10,000,000
Purchase price paid in stock	$ 52,300,000
Class A Common Stock | Warrants | ModSpace
Business Acquisition [Line Items]
Purchase price paid in stock (in shares)	10,000,000
Public Offering | Class A Common Stock
Business Acquisition [Line Items]
Number of shares sold (in shares)		9,200,000
Senior Secured Notes | Senior Notes | ModSpace
Business Acquisition [Line Items]
Proceeds from debt used to fund acquisition	$ 300,000,000
Senior Unsecured Notes | Senior Notes
Business Acquisition [Line Items]
Proceeds from debt used to fund acquisition			$ 200,000,000	$ 200,000,000
Senior Unsecured Notes | Senior Notes | ModSpace
Business Acquisition [Line Items]
Proceeds from debt used to fund acquisition	$ 200,000,000

Business Combinations and Acq_5

Business Combinations and Acquisitions - Stock Consideration Valuation (Details) - ModSpace	Aug. 15, 2018
Expected volatility
Business Acquisition [Line Items]
Stock Consideration fair value inputs	0.286
2018 Warrants fair value inputs	0.350
Risk-free rate of interest
Business Acquisition [Line Items]
Stock Consideration fair value inputs	0.022
2018 Warrants fair value inputs	0.027
Dividend Yield
Business Acquisition [Line Items]
Stock Consideration fair value inputs	0
2018 Warrants fair value inputs	0
Expected life
Business Acquisition [Line Items]
Stock Consideration fair value inputs	0.5
2018 Warrants fair value inputs	4.3

Business Combinations and Acq_6

Business Combinations and Acquisitions - Modspace Unaudited Pro Forma Information (Details) - USD ($)	Aug. 15, 2018	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 19, 2019	Aug. 03, 2018
Business Acquisition [Line Items]
Revenues		$ 437,647,000	$ 417,315,000	$ 256,862,000	$ 255,821,000	$ 278,045,000	$ 268,222,000	$ 263,713,000	$ 253,685,000	$ 1,367,645,000	$ 1,063,665,000	$ 751,412,000
Pretax income (loss)										20,428,000	(13,734,000)	(92,172,000)
Restructuring expenses										6,527,000	3,755,000	15,468,000
Integration costs										18,338,000	26,607,000	30,006,000
Transaction costs										$ 64,053,000	0	20,051,000
ModSpace
Business Acquisition [Line Items]
Pro forma revenues												1,064,021,000
Loss from operations before income tax before pro forma adjustments												(99,629,000)
Pro forma loss from operations before income tax												(111,018,000)
Income tax benefit												(43,462,000)
Pro-forma net loss												$ (67,556,000)
Weighted-average interest rate for borrowings												6.54%
Restructuring expenses												$ 15,500,000
Integration costs											$ 26,600,000	30,000,000
Transaction costs												20,100,000
Interest expense from bridge financing												20,500,000
ModSpace | Trade names
Business Acquisition [Line Items]
Finite-lived intangible assets acquired	$ 3,000,000											$ 3,000,000
Estimated useful lives	3 years											3 years
Impact of fair value mark-ups on rental fleet depreciation | ModSpace
Business Acquisition [Line Items]
Pretax income (loss)												$ 10,135,000
Intangible asset amortization | ModSpace
Business Acquisition [Line Items]
Pretax income (loss)												(625,000)
Interest expense | ModSpace
Business Acquisition [Line Items]
Pretax income (loss)												(41,178,000)
Elimination of interest | ModSpace
Business Acquisition [Line Items]
Pretax income (loss)												20,279,000
ModSpace
Business Acquisition [Line Items]
Revenues												312,609,000
Pretax income (loss)												$ (7,457,000)
Senior Secured Notes | Senior Notes | ModSpace
Business Acquisition [Line Items]
Debt, face amount	$ 300,000,000
Senior Unsecured Notes | Senior Notes
Business Acquisition [Line Items]
Debt, face amount													$ 200,000,000	$ 200,000,000
Senior Unsecured Notes | Senior Notes | ModSpace
Business Acquisition [Line Items]
Debt, face amount	200,000,000
Revolving Credit Facility | 2017 ABL Facility | Line of Credit
Business Acquisition [Line Items]
Weighted-average interest rate for borrowings						4.51%					4.51%
Revolving Credit Facility | 2017 ABL Facility | Line of Credit | ModSpace
Business Acquisition [Line Items]
Amounts drawn on debt	$ 419,000,000

Business Combinations and Acq_7

Business Combinations and Acquisitions - Mobile Mini, Additional Information (Details)	Jul. 01, 2020USD ($)$ / sharesshares	Dec. 31, 2020USD ($)$ / shares
Business Acquisition [Line Items]
Par value (in USD per share) | $ / shares	$ 0.0001	$ 0.0001
Mobile Mini, Inc.
Business Acquisition [Line Items]
Par value (in USD per share) | $ / shares	$ 0.01
Mobile Mini, Inc.
Business Acquisition [Line Items]
Number of shares exchanged (in shares)	2.405
Common stock issued (in shares) | shares	106,426,721
Value of shares converted from acquiree's shares (in USD per share) | $ / shares	$ 12.53
Non-cash investing outflow	$ 1,352,836
Non-cash financing inflow activity	$ 1,352,836
Revenue since acquisition date		$ 316,500,000
Net income since acquisition date		$ 23,100,000

Business Combinations and Acq_8

Business Combinations and Acquisitions - Mobile Mini, Schedule of Consideration Transferred and Purchase Price Allocation (Details) $ / shares in Units, $ in Thousands	Jul. 02, 2020shares	Jul. 01, 2020USD ($)$ / sharesshares	Dec. 31, 2020shares
Business Acquisition [Line Items]
Mobile Mini Common Stock outstanding (in shares)			229,038,158
Mobile Mini, Inc.
Business Acquisition [Line Items]
Mobile Mini Common Stock outstanding (in shares)		44,252,275
Mobile Mini, Inc.
Business Acquisition [Line Items]
Number of shares exchanged (in shares)		2.405
Common stock issued (in shares)		106,426,721
Common Stock per share price as of July 1, 2020 (in USD per share) | $ / shares		$ 12.53
Cash consideration | $		$ 30
Consideration | $		$ 1,352,836
Mobile Mini, Inc. | Common Stock
Business Acquisition [Line Items]
Common stock issued (in shares)		106,426,721
Common Stock per share price as of July 1, 2020 (in USD per share) | $ / shares		$ 12.53
Purchase price paid in stock | $		$ 1,333,527
Mobile Mini, Inc. | Stock Options
Business Acquisition [Line Items]
Number of shares exchanged (in shares)	2.405
Common stock issued (in shares)	7,361,516	7,361,516
Purchase price paid in stock | $		$ 19,279

Business Combinations and Acq_9

Business Combinations and Acquisitions - Mobile Mini, Inc., Assets and Liabilities Acquired (Details) - USD ($) $ in Thousands	Jul. 01, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Goodwill		$ 1,171,219	$ 235,177	$ 247,017
Mobile Mini, Inc.
Business Acquisition [Line Items]
Consideration	$ 1,352,836
Cash and cash equivalents		17,203
Trade receivables		87,492
Inventories		8,987
Prepaid expenses and other current assets		13,264
Rental equipment		1,033,190
Property, plant and equipment, net		161,401
Operating lease assets		92,054
Intangible assets		382,500
Goodwill		928,974
Other non-current assets		2,387
Total identifiable assets acquired		2,727,452
Accounts payable		(29,797)
Accrued liabilities and interest		(38,759)
Deferred revenue and customer deposits		(38,846)
Operating lease liabilities		(89,968)
Debt and finance lease liabilities		(897,244)
Deferred tax liabilities		(278,727)
Other long-term liabilities		(1,275)
Total liabilities assumed		(1,374,616)
Net assets acquired (purchase price)		1,352,836
Trade receivable, gross		99,800
Rental equipment, adjustment		(109,800)
Intangible assets, adjustments		(183,100)
Property, plant and equipment, net		8,200
Deferred tax liabilities		$ (68,000)

Business Combinations and Ac_10

Business Combinations and Acquisitions - Mobile Mini, Pro Forma Information (Details) - USD ($) $ in Thousands	Jul. 01, 2020	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 15, 2020
Business Acquisition [Line Items]
Revenues		$ 437,647	$ 417,315	$ 256,862	$ 255,821	$ 278,045	$ 268,222	$ 263,713	$ 253,685	$ 1,367,645	$ 1,063,665	$ 751,412
Pretax income (loss)										20,428	(13,734)	(92,172)
Income tax benefit due to reversal of valuation allowance										$ 56,479	(961)	$ 11,871
2025 Secured Notes | Senior Notes
Business Acquisition [Line Items]
Interest rate		6.125%								6.125%			6.125%
Revolving Credit Facility | 2020 ABL Facility | Line of Credit
Business Acquisition [Line Items]
Amounts drawn on debt	$ 1,470,000
Implicit interest rate	2.046%
Mobile Mini, Inc.
Business Acquisition [Line Items]
Revenues										$ 284,240	620,018
Mobile Mini, Inc.
Business Acquisition [Line Items]
Pro forma revenues										1,651,885	1,683,683
Pretax income (loss)										154,914	110,173
Pro forma pretax income										58,303	97,971
Income tax expense										(34,549)	(28,892)
Pro forma net income										120,365	81,281
Intangible assets		$ 382,500								382,500
Income tax benefit due to reversal of valuation allowance										54,600
Mobile Mini, Inc. | Mobile Mini customer relationships
Business Acquisition [Line Items]
Intangible assets	$ 263,000
Estimated useful lives	13 years
Mobile Mini, Inc. | Elimination of Merger transaction costs
Business Acquisition [Line Items]
Pretax income (loss)										80,852	0
Mobile Mini, Inc. | Impact of fair value mark-ups on rental fleet depreciation
Business Acquisition [Line Items]
Pretax income (loss)										(2,334)	(4,667)
Mobile Mini, Inc. | Other depreciation expense and intangible asset amortization
Business Acquisition [Line Items]
Pretax income (loss)										(11,397)	(22,399)
Mobile Mini, Inc. | Interest expense
Business Acquisition [Line Items]
Pretax income (loss)										(6,113)	(1,916)
Mobile Mini, Inc. | Elimination of interest
Business Acquisition [Line Items]
Pretax income (loss)										15,921	39,672
Mobile Mini, Inc. | Elimination of loss on extinguishment of debt
Business Acquisition [Line Items]
Pretax income (loss)										19,682	1,512
Mobile Mini, Inc. | Mobile Mini, Inc.
Business Acquisition [Line Items]
Pretax income (loss)										$ 37,875	$ 111,705

Business Combinations and Ac_11

Business Combinations and Acquisitions - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Transaction costs		$ 64,053	$ 0	$ 20,051
Integration costs		18,338	26,607	30,006
Mobile Mini, Inc.
Business Acquisition [Line Items]
Transaction costs		$ 64,100
Integration costs	$ 16,600
ModSpace
Business Acquisition [Line Items]
Transaction costs				20,100
Integration costs			$ 26,600	30,000
Tyson, Acton, and ModSpace acquisitions
Business Acquisition [Line Items]
Integration costs				$ 30,000

Revenue - Revenue Disaggregatio

Revenue - Revenue Disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Total revenue	$ 437,647	$ 417,315	$ 256,862	$ 255,821	$ 278,045	$ 268,222	$ 263,713	$ 253,685	$ 1,367,645	$ 1,063,665	$ 751,412
US
Disaggregation of Revenue [Line Items]
Total revenue									1,227,465	966,766	685,350
Canada
Disaggregation of Revenue [Line Items]
Total revenue									79,630	80,514	50,144
Mexico
Disaggregation of Revenue [Line Items]
Total revenue									14,190	16,385	15,918
UK
Disaggregation of Revenue [Line Items]
Total revenue									46,360	0	0
Modular space leasing revenue
Disaggregation of Revenue [Line Items]
Total revenue									596,880	516,299	360,240
Portable storage leasing revenue
Disaggregation of Revenue [Line Items]
Total revenue									125,216	24,277	21,682
Tank and Pump
Disaggregation of Revenue [Line Items]
Total revenue									29,798	0	0
VAPS and third party leasing revenue
Disaggregation of Revenue [Line Items]
Total revenue									202,938	159,327	104,870
Other leasing-related revenue
Disaggregation of Revenue [Line Items]
Total revenue									46,615	44,282	31,443
Leasing revenue
Disaggregation of Revenue [Line Items]
Total revenue									1,001,447	744,185	518,235
Delivery and installation revenue
Disaggregation of Revenue [Line Items]
Total revenue									274,156	220,057	154,557
Total leasing and services revenue
Disaggregation of Revenue [Line Items]
Total revenue	$ 409,622	$ 384,776	$ 241,783	$ 239,422	$ 245,755	$ 249,411	$ 241,784	$ 227,292	1,275,603	964,242	672,792
New units
Disaggregation of Revenue [Line Items]
Total revenue									53,093	59,085	53,603
Rental units
Disaggregation of Revenue [Line Items]
Total revenue									38,949	40,338	25,017
VAPS service revenue
Disaggregation of Revenue [Line Items]
Total revenue									$ 18,800	$ 15,900	$ 10,800

Revenue - Additional Informatio

Revenue - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Provision for credit losses, net of recoveries		$ 13.4	$ 4.5	$ 7.7
Provision for credit losses recorded as a reduction to revenue for the provision of specific receivables whole collection is not considered probable		18	10
Deferred revenue for removal services for lease transactions and advance billings for sale transactions	$ 74.1	$ 74.1	42.6
Recognition of previously deferred revenue for removal services for lease transactions and advance billings for sale transactions	$ 37.5		$ 14
Trade receivables, net of allowances for credit losses | Credit Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration risk, percentage		4.90%	4.10%
Leasing revenue | Revenue | Product Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration risk, percentage		72.00%	68.00%	68.00%

Revenue - Future Commited Modul

Revenue - Future Commited Modular Leasing Revenues (Details) $ in Thousands	Dec. 31, 2020USD ($)
Revenue from Contract with Customer [Abstract]
2021	$ 232,730
2022	75,664
2023	29,419
2024	11,643
2025	4,284
Thereafter	2,738
Total	$ 356,478

Leases - Lease Maturity (Detail

Leases - Lease Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Operating
2021	$ 60,120	$ 37,648
2022	51,184	33,903
2023	41,074	27,769
2024	33,336	21,926
2025	26,542	16,685
Thereafter	67,421	47,916
Total lease payments	279,677	185,847
Less: interest	(47,853)	(38,285)
Present value of lease liabilities	231,824	147,562	$ 138,500
Finance
2021	18,252	0
2022	17,158	0
2023	13,707	0
2024	10,786	0
2025	10,893	0
Thereafter	13,410	0
Total lease payments	84,206	0
Less: interest	(6,332)	0
Present value of lease liabilities	$ 77,874	$ 0

Leases - Lease Cost (Details)

Leases - Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Finance Lease Expense
Amortization of finance lease assets	$ 9,556	$ 0
Interest on obligations under finance leases	1,081	0
Total finance lease expense	10,637	0
Operating Lease Expense
Total operating lease expense	93,391	83,224
Cost of leasing and services
Operating Lease Expense
Fixed lease expense	5,723	6,737
Short-term lease expense	25,576	29,729
Variable lease expense	6,981	3,787
Selling, general and administrative
Operating Lease Expense
Fixed lease expense	43,482	34,058
Short-term lease expense	2,067	2,071
Variable lease expense	5,436	4,231
Lease impairment expense and other related charges
Operating Lease Expense
Fixed lease expense	2,800	2,611
Short-term lease expense	471	0
Variable lease expense	$ 855	$ 0

Leases - Narrative (Details)

Leases - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Lease impairment expense and other related charges	$ 4,876	$ 8,674	$ 0
Loss on lease exit and impairment charges	700
ROU asset impairment	57	4,160
Loss on lease exit		1,900
Closed location rent expense	$ 4,200	$ 2,600
Rent expense			$ 31,000

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating cash outflows from operating leases	$ 45,883	$ 42,111
Financing cash outflows from finance leases	9,568	0
Right of use assets obtained in exchange for lease obligations	33,576	43,013
Assets obtained in exchange for finance leases	$ 9,089	$ 0

Leases - Lease Terms and Discou

Leases - Lease Terms and Discount Rates (Details)	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Weighted-average remaining lease term - operating leases	6 years 4 months 24 days	6 years 6 months
Weighted-average discount rate - operating leases	5.70%	7.00%
Weighted-average remaining lease term - finance leases	4 years 7 months 6 days
Weighted-average discount rate - finance leases	2.90%

Inventories - Schedule of Inven

Inventories - Schedule of Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 19,560	$ 15,387
Finished units	2,095	0
Inventories	$ 21,655	$ 15,387

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Tax receivables	$ 4,618	$ 1,211
Prepaid insurance	5,859	2,099
Other prepaid expenses	19,477	11,311
Total prepaid expenses and other current assets	$ 29,954	$ 14,621

Rental Equipment, Net - Rental

Rental Equipment, Net - Rental Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Modular space units
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 2,520,704	$ 2,372,069
Portable storage units
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	931,363	83,402
Tank and pump equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	132,071	0
Value added products
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	143,652	121,855
Total rental equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	3,727,790	2,577,326
Less: accumulated depreciation	(794,068)	(632,890)
Property, plant and equipment, net	$ 2,933,722	$ 1,944,436

Property, Plant and Equipment_3

Property, Plant and Equipment, net - Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Land, buildings, and leasehold improvements
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 154,210	$ 139,861
Vehicles, machinery, and equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	227,009	62,169
Software
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	20,800	27,342
Total property, plant and equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	402,019	229,372
Less: accumulated depreciation	(98,369)	(81,683)
Property, plant and equipment, net	$ 303,650	$ 147,689

Property, Plant and Equipment_4

Property, Plant and Equipment, net - Narrative (Details) - Total property, plant and equipment - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 28,900,000	$ 11,400,000	$ 12,200,000
Gross cost of property, plant and equipment assets under finance leases	78,700,000	$ 0
Accumulated depreciation of property, plant and equipment assets under finance leases	$ 9,500,000

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Goodwill Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Goodwill, beginning of period	$ 235,177	$ 247,017
Changes to purchase price accounting - Modspace		(13,479)
Acquisition of Mobile Mini	928,974
Effects of movements in foreign exchange rates	7,068	1,639
Goodwill, end of period	1,171,219	235,177
NA Storage
Goodwill [Roll Forward]
Goodwill, beginning of period	0
Acquisition of Mobile Mini	726,500
Goodwill, end of period	726,529	0
UK Storage
Goodwill [Roll Forward]
Goodwill, beginning of period	0
Acquisition of Mobile Mini	59,200
Goodwill, end of period	65,600	0
Tank and Pump
Goodwill [Roll Forward]
Goodwill, beginning of period	0
Acquisition of Mobile Mini	143,300
Goodwill, end of period	$ 143,262	$ 0

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Narrative (Details) - USD ($) $ in Millions	Aug. 15, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jul. 01, 2020
Finite-Lived Intangible Assets [Line Items]
Accumulated impairment loss		$ 792.8	$ 792.8	$ 792.8
Amortization expense		$ 14.4	$ 1
Mobile Mini, Inc.
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets acquired					$ 164
Definite-lived intangible assets acquired					$ 218.5
ModSpace | Trade names
Finite-Lived Intangible Assets [Line Items]
Definite-lived intangible assets acquired	$ 3			$ 3
Estimated useful lives	3 years			3 years

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Intangible assets subject to amortization:
Gross carrying amount		$ 3,000
Accumulated amortization	$ (14,553)	(1,375)
Net book value	206,947	1,625
Indefinite-lived intangible assets:
Gross carrying amount	510,500	128,000
Net book value	$ 495,947	$ 126,625
Trade name - ModSpace
Intangible assets subject to amortization:
Weighted average remaining life (in years)	8 months 12 days	1 year 8 months 12 days
Gross carrying amount	$ 3,000	$ 3,000
Accumulated amortization	(2,375)	(1,375)
Net book value	$ 625	1,625
Mobile Mini customer relationships
Intangible assets subject to amortization:
Weighted average remaining life (in years)	8 years
Gross carrying amount	$ 217,000
Accumulated amortization	(12,053)
Net book value	$ 204,947
Technology
Intangible assets subject to amortization:
Weighted average remaining life (in years)	5 years 6 months
Gross carrying amount	$ 1,500
Accumulated amortization	(125)
Net book value	1,375
Trade name - Mobile Mini
Indefinite-lived intangible assets:
Net book value	164,000
Trade name - WillScot
Indefinite-lived intangible assets:
Net book value	$ 125,000	$ 125,000

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets - Future Amortization (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
2021	$ 27,167
2022	26,542
2023	26,542
2024	26,542
2025	26,542
Thereafter	73,612
Net book value	$ 206,947	$ 1,625

Deferred Revenue and Customer_3

Deferred Revenue and Customer Deposits (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current:
Deferred revenue	$ 133,156	$ 81,303
Customer deposits	2,329	1,675
Total current deferred revenue and customer deposits	135,485	82,978
Long-term:
Deferred revenue	12,060	12,342
Total long-term deferred revenue and customer deposits	$ 12,060	$ 12,342

Debt - Carrying Value of Debt O

Debt - Carrying Value of Debt Outstanding (Details) - USD ($)	Dec. 31, 2020	Aug. 25, 2020	Jun. 15, 2020	Dec. 31, 2019	May 14, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Finance Leases	$ 77,874,000			$ 0
Total debt	2,470,330,000			1,632,589,000
Current portion of long-term debt	16,521,000			0
Total long-term debt	2,453,809,000			1,632,589,000
Senior Notes | 2022 Secured Notes
Debt Instrument [Line Items]
Debt	$ 0			264,576,000
Interest rate	7.875%						7.875%
Debt issuance costs				5,400,000
Senior Notes | 2023 Secured Notes
Debt Instrument [Line Items]
Debt	$ 0			482,768,000
Interest rate	6.875%				6.875%	6.875%
Senior Notes | 2025 Secured Notes
Debt Instrument [Line Items]
Debt	$ 637,068,000			0
Interest rate	6.125%		6.125%
Debt issuance costs	$ 12,900,000		$ 14,300,000
Senior Notes | 2028 Secured Notes
Debt Instrument [Line Items]
Debt	$ 491,555,000			0
Interest rate	4.625%	4.625%
Debt issuance costs	$ 8,400,000
Line of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Debt	1,263,833,000			885,245,000
Outstanding principal borrowings on the credit facility	0
Line of Credit | Canadian ABL Facility
Debt Instrument [Line Items]
Debt issuance costs				0
Line of Credit | Canadian ABL Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Debt				0
Debt issuance costs				$ 2,100,000
Line of Credit | 2020 Multicurrency ABL Facility
Debt Instrument [Line Items]
Debt issuance costs	0
Line of Credit | 2020 Multicurrency ABL Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Debt issuance costs	$ 7,900,000

Debt - Maturities of Debt and L

Debt - Maturities of Debt and Lease Obligation (Details) $ in Thousands	Dec. 31, 2020USD ($)
Debt Disclosure [Abstract]
2021	$ 18,252
2022	17,158
2023	13,707
2024	10,786
2025	1,965,505
Thereafter	$ 513,410

Debt - Debt Discount Amortizati

Debt - Debt Discount Amortization (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Debt Disclosure [Abstract]
2021	$ 14,317,000
2022	14,540,000
2023	14,778,000
2024	15,031,000
2025	8,050,000
Thereafter	$ 3,365,000

Debt - ABL Facilities, Addition

Debt - ABL Facilities, Additional Information (Details) - USD ($)	Jul. 01, 2020	Nov. 29, 2017	Dec. 31, 2020	Dec. 31, 2019
Line of Credit Facility [Line Items]
Finance Leases			$ 77,874,000	$ 0
2017 ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Letters of credit amount outstanding			12,700,000
Revolving Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Outstanding principal borrowings on the credit facility			0
Revolving Credit Facility | 2017 ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility		$ 1,425,000,000		$ 1,425,000,000
Accordion feature		$ 375,000,000
Applicable margin, step down		0.25%
Applicable margin, step up		0.25%
Commitment fee				2.875%
Weighted-average interest rate for borrowings				4.51%
Weighted-average interest rate for borrowings after derivative instruments				5.10%
Available borrowing capacity				$ 509,100,000
Outstanding principal borrowings on the credit facility				903,000,000
Debt issuance costs and discounts				17,800,000
Repayments of debt	$ 1,470,000,000
Write off of debt issuance costs	4,400,000
Revolving Credit Facility | 2017 US ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility		$ 1,285,000,000
Available borrowing capacity				369,300,000
Revolving Credit Facility | 2017 Canadian ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility		$ 140,000,000
Available borrowing capacity				139,800,000
Revolving Credit Facility | 2020 ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility	2,400,000,000		$ 2,400,000,000
Commitment fee			0.225%
Weighted-average interest rate for borrowings			2.05%
Available borrowing capacity			$ 1,100,000,000
Letters of credit amount outstanding			14,400,000
Outstanding principal borrowings on the credit facility			1,300,000,000
Debt issuance costs and discounts			$ 40,800,000
Revolving Credit Facility | 2020 ABL Facility | Line of Credit | Interest Rate Swap
Line of Credit Facility [Line Items]
Weighted-average interest rate for borrowings after derivative instruments			2.94%
Revolving Credit Facility | 2020 US ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility	2,000,000,000
Available borrowing capacity			$ 681,000,000
Revolving Credit Facility | 2020 Multicurrency ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility	$ 400,000,000
Available borrowing capacity			$ 400,000,000
Letter of Credit | 2017 ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Commitment fee			2.00%
Letter of Credit | 2017 US ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility				75,000,000
Letter of Credit | 2017 Canadian ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility				60,000,000
Letter of Credit | 2020 ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility			$ 205,600,000
Swingline Loans | 2017 US ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility				75,000,000
Swingline Loans | 2017 Canadian ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility				$ 50,000,000
Swingline Loans | 2020 ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility			$ 170,000,000
LIBOR | Revolving Credit Facility | 2017 ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Applicable margin		2.50%
LIBOR | Revolving Credit Facility | 2020 ABL Facility | Line of Credit | US Dollars
Line of Credit Facility [Line Items]
Applicable margin	1.875%
Base Rate | Revolving Credit Facility | 2017 ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Applicable margin		1.50%
Base Rate | Revolving Credit Facility | 2020 ABL Facility | Line of Credit | US Dollars
Line of Credit Facility [Line Items]
Applicable margin	0.875%
BA Rate | Revolving Credit Facility | 2020 ABL Facility | Line of Credit | Canadian Dollars
Line of Credit Facility [Line Items]
Applicable margin	1.875%
BA Rate | Revolving Credit Facility | 2020 ABL Facility | Line of Credit | British Pounds Sterling
Line of Credit Facility [Line Items]
Applicable margin	1.875%
BA Rate | Revolving Credit Facility | 2020 ABL Facility | Line of Credit | Euro
Line of Credit Facility [Line Items]
Applicable margin	1.875%
Prime Rate | Revolving Credit Facility | 2020 ABL Facility | Line of Credit | Canadian Dollars
Line of Credit Facility [Line Items]
Applicable margin	0.875%
Minimum | Revolving Credit Facility | 2017 ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Commitment fee		0.375%
Maximum | Revolving Credit Facility | 2017 ABL Facility | Line of Credit
Line of Credit Facility [Line Items]
Commitment fee		0.50%

Debt - 2022 Senior Secured Note

Debt - 2022 Senior Secured Notes, Additional Information (Details) - USD ($)	Dec. 13, 2019	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Loss on extinguishment of debt			$ 42,401,000	$ 8,755,000	$ 0
2022 Secured Notes | Senior Notes
Debt Instrument [Line Items]
Debt, face amount						$ 300,000,000
Interest rate			7.875%			7.875%
Repayments of debt	$ 30,000,000
Redemption price	103.00%
Loss on extinguishment of debt	$ 1,500,000	$ 15,200,000
Early redemption premium	900,000	10,600,000
Write off of debt issuance costs	$ 600,000	$ 4,600,000
Unamortized debt issuance costs				$ 5,400,000

Debt - 2023 Senior Secured Note

Debt - 2023 Senior Secured Notes, Additional Information (Details) - USD ($)	Aug. 25, 2020	Aug. 11, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	May 14, 2019
Debt Instrument [Line Items]
Loss on extinguishment of debt			$ 42,401,000	$ 8,755,000	$ 0
2023 Secured Notes | Senior Notes
Debt Instrument [Line Items]
Debt, face amount					$ 300,000,000	$ 490,000,000
Interest rate			6.875%		6.875%	6.875%
Redemption percentage of aggregate principal amount		10.00%
Repayments of debt	$ 441,000,000	$ 49,000,000
Redemption price	103.438%	103.00%
Loss on extinguishment of debt	$ 22,700,000
Early redemption premium	16,600,000
Write off of debt issuance costs	$ 6,100,000
Debt issuance costs and discounts			$ 7,200,000
2023 Secured Notes, Tack-on Offering | Senior Notes
Debt Instrument [Line Items]
Debt, face amount						$ 190,000,000
Debt issuance costs						$ 3,000,000

Debt - 2025 Senior Secured Note

Debt - 2025 Senior Secured Notes, Additional Information (Details) - 2025 Secured Notes - Senior Notes - USD ($)	Jun. 15, 2020	Aug. 01, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Debt, face amount	$ 650,000,000
Interest rate	6.125%		6.125%
Interest expense		$ 5,100,000
Debt issuance costs	$ 14,300,000		$ 12,900,000
Redemption Period One | 100% of Principal
Debt Instrument [Line Items]
Redemption price	100.00%
Redemption Period One | 40% of Principal
Debt Instrument [Line Items]
Redemption price	106.125%
Redemption percentage of aggregate principal amount	40.00%
Redemption Period One | 10% of Principal
Debt Instrument [Line Items]
Redemption price	103.00%
Redemption percentage of aggregate principal amount	10.00%

Debt - Redemption Price Percent

Debt - Redemption Price Percentage (Details) - Senior Notes	12 Months Ended
	Dec. 31, 2020
2025 Secured Notes | Redemption Period Two
Debt Instrument [Line Items]
Redemption price	103.063%
2025 Secured Notes | Redemption Period Three
Debt Instrument [Line Items]
Redemption price	101.531%
2025 Secured Notes | Redemption Period Four
Debt Instrument [Line Items]
Redemption price	100.00%
2028 Secured Notes | Redemption Period Two
Debt Instrument [Line Items]
Redemption price	102.313%
2028 Secured Notes | Redemption Period Three
Debt Instrument [Line Items]
Redemption price	101.156%
2028 Secured Notes | Redemption Period Four
Debt Instrument [Line Items]
Redemption price	100.00%

Debt - 2028 Senior Secured Note

Debt - 2028 Senior Secured Notes, Additional Information (Details) - 2028 Secured Notes - Senior Notes - USD ($)	Aug. 25, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Debt, face amount	$ 500,000,000
Interest rate	4.625%	4.625%
Debt issuance costs		$ 8,400,000
100% of Principal | Redemption Period One
Debt Instrument [Line Items]
Redemption Price	100.00%
40% of Principal | Redemption Period One
Debt Instrument [Line Items]
Redemption Price	104.625%
Redemption percentage of aggregate principal amount	40.00%
10% of Principal | Redemption Period One
Debt Instrument [Line Items]
Redemption Price	103.00%
Redemption percentage of aggregate principal amount	10.00%

Debt - 2023 Senior Unsecured No

Debt - 2023 Senior Unsecured Notes (Details) - USD ($)	Jun. 19, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Aug. 03, 2018
Debt Instrument [Line Items]
Loss on extinguishment of debt		$ 42,401,000	$ 8,755,000	$ 0
Senior Notes | 2023 Senior Unsecured Notes
Debt Instrument [Line Items]
Debt, face amount	$ 200,000,000				$ 200,000,000
Redemption Price		102.00%
Make-whole premium	1.126%
Loss on extinguishment of debt	$ 7,200,000
Early redemption premium	6,200,000
Write off of debt issuance costs	$ 1,000,000

Debt - Finance Leases, Addition

Debt - Finance Leases, Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
Finance Leases	$ 77,874	$ 0

Debt - Mobile Mini Debt, Additi

Debt - Mobile Mini Debt, Additional Information (Details) - Mobile Mini, Inc.	Jun. 30, 2020USD ($)
Line of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility	$ 1,000,000,000
Outstanding principal	563,200,000
5.875% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Debt, face amount	$ 250,000,000
Interest rate	5.875%

Equity - Additional Information

Equity - Additional Information (Details) - USD ($)	Jul. 01, 2020	Jun. 30, 2020	Dec. 11, 2018	Nov. 08, 2018	Aug. 15, 2018	Aug. 10, 2018	Jul. 30, 2018	Feb. 24, 2020	Jan. 24, 2020	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2015	Aug. 07, 2020
Class of Stock [Line Items]
Preferred shares authorized (in shares)											1,000,000	1,000,000	1,000,000	1,000,000
Preferred share par value (in USD per share)											$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Preferred shares issued (in shares)											0	0	0	0
Preferred shares outstanding (in shares)											0	0	0	0
Common stock authorized (in shares)											500,000,000	500,000,000	500,000,000
Common stock par value (in USD per share)	$ 0.0001										$ 0.0001	$ 0.0001	$ 0.0001
Common stock issued (in shares)											229,038,158	229,038,158	229,038,158
Common stock outstanding (in shares)											229,038,158	229,038,158	229,038,158
Discounts and offering expenses													$ 4,222,000	$ 0	$ 0
Shares issued for warrant exchange (in shares)			8,205,841
Stock-based compensation and issuance of Common Stock from vesting (in shares)													13,792,582	309,857
Shares issued for each share converted (in shares)		1.3261
Shares issued for conversion (in shares)		10,641,182
Shares issued for conversion													$ 0
Authorized share repurchase program																	$ 250,000,000
Shares repurchased (in shares)											0
Warrants and share equivalents repurchased, including witholding taxes													35,300,000
Non-cash deemed dividend related to warrant exchange													0	$ 0	$ 2,135,000
Non-Controlling Interest
Class of Stock [Line Items]
Shares issued for conversion		$ 63,900,000											(63,918,000)
Additional Paid-in Capital
Class of Stock [Line Items]
Shares issued for conversion		66,900,000											66,890,000
Accumulated Other Comprehensive Income (Loss)
Class of Stock [Line Items]
Shares issued for conversion		$ (3,000,000)											$ (2,972,000)
ModSpace
Class of Stock [Line Items]
Warrant exercise price (in USD per share)					$ 15.50
Mobile Mini, Inc.
Class of Stock [Line Items]
Shares issued as part of consideration for acquisition (in shares)	106,426,722
Purchase price paid in stock (in shares)	106,426,721
Public Warrants
Class of Stock [Line Items]
Discounts and offering expenses										$ 1,800,000
Shares issued for warrant exchange (in shares)				8,205,841
Warrant exercise price per half share (in USD per share)																$ 5.75
Warrant exercise price (in USD per share)																11.50
Warrant redemption price (in USD per share)											$ 0.01	$ 0.01	$ 0.01			0.01
Minimum share price for warrant redemption (in USD per share)																$ 18
Threshold trading days for warrant redemption																20 days
Threshold consecutive trading days for warrant redemption																30 days
Notice period for redemption of warrants																30 days
Number of shares warrant holders are entitled to purchase (in shares)				0.18182
Number of warrants exchanged (in shares)				45,131,827
Warrants outstanding (in shares)				69,499,694							0	0	0
Non-cash deemed dividend related to warrant exchange				$ 2,100,000
Warrants exercised (in shares)								5,836,048	796,610			38,509
Proceeds from warrant exercises									$ 4,600,000
Common stock issued in warrant exchange (in shares)								1,097,162	398,305
Private Placement Warrants
Class of Stock [Line Items]
Warrants outstanding (in shares)											12,710,000	12,710,000	12,710,000
Warrants exercised (in shares)													70,000
Proceeds from warrant exercises													$ 400,000
Common stock issued in warrant exchange (in shares)													35,000
Purchase price for warrants (in USD per share)																$ 0.50
Purchase price for warrants																$ 9,750,000
Number of warrants repurchased and terminated (in shares)													4,781,700
Warrants repurchased and terminated													$ 21,600,000
2018 Warrants
Class of Stock [Line Items]
Warrant exercise price (in USD per share)					$ 15.50
Number of shares warrant holders are entitled to purchase (in shares)					1
Warrants outstanding (in shares)											9,730,241	9,730,241	9,730,241
Warrants exercised (in shares)													195,410
Common stock issued in warrant exchange (in shares)													38,802
Number of warrants repurchased and terminated (in shares)													51,865
Warrants repurchased and terminated													$ 300,000
Class A Common Stock
Class of Stock [Line Items]
Common stock authorized (in shares)														400,000,000
Common stock par value (in USD per share)	$ 0.0001													$ 0.0001
Common stock issued (in shares)														108,818,854
Common stock outstanding (in shares)														108,818,854
Common stock issued in warrant exchange (in shares)															8,206,000
Class B Common Stock
Class of Stock [Line Items]
Common stock authorized (in shares)														100,000,000
Common stock par value (in USD per share)		$ 0.0001												$ 0.0001
Common stock issued (in shares)														8,024,419
Common stock outstanding (in shares)														8,024,419
Public Offering
Class of Stock [Line Items]
Number of shares sold (in shares)							8,000,000
Share price (in USD per share)							$ 16
Purchase price of shares sold							$ 139,000,000
Discounts and offering expenses							$ 8,200,000
Underwriter's Option
Class of Stock [Line Items]
Number of shares sold (in shares)						1,200,000
Common Stock | ModSpace
Class of Stock [Line Items]
Shares issued as part of consideration for acquisition (in shares)					6,458,229
Purchase price paid in stock (in shares)					6,458,229
Common Stock | Mobile Mini, Inc.
Class of Stock [Line Items]
Purchase price paid in stock (in shares)	106,426,721
Warrants | ModSpace
Class of Stock [Line Items]
Purchase price paid in stock (in shares)					10,000,000
Warrants | Class A Common Stock | ModSpace
Class of Stock [Line Items]
Purchase price paid in stock (in shares)					10,000,000

Equity - Accumulated Other Comp

Equity - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	Jan. 01, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance		$ 644,365
Other comprehensive income (loss) before reclassifications		16,530	$ 2,656	$ (17,879)
Reclassifications from AOCI to income		10,125	3,121	285
Reclassifications from AOCI to retained earnings	$ 2,500			0
Less other comprehensive income (loss) attributable to non-controlling interest		1,885	(526)	1,605
Impact of elimination of non-controlling interest on accumulated other comprehensive income		(2,972)
Ending balance		2,141,277	644,365
Foreign Currency Translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(49,497)	(52,982)	(62,608)	(49,497)
Other comprehensive income (loss) before reclassifications		28,404	10,586	(11,639)
Reclassifications from AOCI to income		0	0	0
Reclassifications from AOCI to retained earnings				(2,540)
Less other comprehensive income (loss) attributable to non-controlling interest		1,183	(960)	1,068
Impact of elimination of non-controlling interest on accumulated other comprehensive income		(1,299)
Ending balance		(24,694)	(52,982)	(62,608)
Unrealized losses on hedging activities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0	(9,793)	(5,418)	0
Other comprehensive income (loss) before reclassifications		(11,874)	(7,930)	(6,240)
Reclassifications from AOCI to income		10,125	3,121	285
Reclassifications from AOCI to retained earnings				0
Less other comprehensive income (loss) attributable to non-controlling interest		702	434	537
Impact of elimination of non-controlling interest on accumulated other comprehensive income		(1,673)
Ending balance		(12,513)	(9,793)	(5,418)
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ (49,497)	(62,775)	(68,026)	(49,497)
Reclassifications from AOCI to retained earnings				(2,540)
Ending balance		(37,207)	(62,775)	(68,026)
Interest Rate Swap | Unrealized losses on hedging activities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications from AOCI to income		10,100	3,300	400
Tax benefit from reclassification from AOCI to income		$ 2,400	$ 800	$ 100

Income Taxes - Components of In

Income Taxes - Components of Income Tax Benefit (Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
US Federal and State
Current	$ 1,601	$ 827	$ 668
Deferred	(58,026)	1,904	(36,149)
Outside of US
Current	2,104	(395)	924
Deferred	2,870	(4,527)	(4,043)
Total income tax benefit	$ (51,451)	$ (2,191)	$ (38,600)

Income Taxes - Income Tax Rate

Income Taxes - Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income (loss) before income tax
US	$ 3,136	$ (9,477)	$ (80,824)
Non-US	17,292	(4,257)	(11,348)
Income (loss) before tax	20,428	(13,734)	(92,172)
US Federal statutory income tax expense (benefit)	4,290	(2,884)	(19,356)
Effect of tax rates in foreign jurisdictions	128	(207)	(626)
State income tax expense (benefit), net of federal benefit	3,962	1,829	(2,478)
Unremitted foreign earnings	0	0	(6,793)
Valuation allowances	(56,479)	961	(11,871)
Non-deductible items	187	(233)	0
Non-deductible executive compensation	1,449	490	0
Non-deductible transaction costs	4,425	(12)	1,134
Uncertain tax positions	(11,166)	0	0
Tax law changes (Excluding valuation allowance)	2,523	(2,785)	64
Other	(770)	650	1,326
Total income tax benefit	$ (51,451)	$ (2,191)	$ (38,600)
Effective income tax rate	(251.87%)	15.95%	41.88%

Income Taxes - Components of De

Income Taxes - Components of Deferred Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets
Deferred interest expense	$ 128,346	$ 138,206
Employee benefit plans	3,532	1,916
Accrued liabilities	10,692	8,494
Deferred revenue	32,412	20,951
Operating lease liability	58,044	37,438
Other	13,628	7,817
Tax loss carryforwards	295,326	231,503
Deferred tax assets, gross	541,980	446,325
Valuation allowance	(25,158)	(80,241)
Net deferred income tax asset	516,822	366,084
Deferred tax liabilities
Rental equipment and other property, plant and equipment	(648,966)	(375,682)
Intangible assets	(117,403)	(23,690)
ROU asset	(57,820)	(37,218)
Deferred tax liability	(824,189)	(436,590)
Net deferred income tax liability	$ (307,367)	$ (70,506)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Change in deferred tax asset valuation allowance		$ (55,100)
Change in valuation allowance from business combination		1,500
Change in valuation allowance from change in estimate in realizability		(56,600)
Deferred tax asset valuation allowance		25,158	$ 80,241
Change in valuation allowance from change in estimate of future income	$ (54,600)
Undistributed foreign earnings		327,300
Unrecognized tax benefits that, if recognized, would affect the annual effective tax rate		53,200	59,300	$ 60,000
Income tax interest and penalties		(900)	800	$ 1,000
Income tax interest and penalties accrued		1,500	$ 2,400
Decrease in unrecognized tax benefits that are reasonably possible could decrease in next twelve months		$ 11,300

Income Taxes - Income Loss Carr

Income Taxes - Income Loss Carryforwards (Details) $ in Millions	Dec. 31, 2020USD ($)
Operating Loss Carryforwards [Line Items]
Loss Carryforward	$ 1,902.1
US - Federal
Operating Loss Carryforwards [Line Items]
Loss Carryforward	1,187.5
US - State
Operating Loss Carryforwards [Line Items]
Loss Carryforward	700.5
Foreign - Mexico & Canada
Operating Loss Carryforwards [Line Items]
Loss Carryforward	$ 14.1

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits – January 1,	$ 63,747	$ 64,444	$ 72,660
Increases based on tax positions related to current period	1,211	0	1,545
Increases based on tax positions related to prior period	0	268	0
Decreases based on tax positions related to prior period	0	(287)	(9,016)
Decrease from expiration of statute of limitations	(10,464)	(678)	(745)
Unrecognized tax benefits – December 31,	$ 54,494	$ 63,747	$ 64,444

Derivatives - Narrative (Detail

Derivatives - Narrative (Details) - Interest Rate Swap - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Notational amount	$ 400,000,000
Pay rate	3.06%
Receive rate	0.15%	1.74%

Derivatives - Location and Fair

Derivatives - Location and Fair Value of Derivative Instruments Designated as Hedges in the Consolidated Balance Sheet (Details) - Interest Rate Swap - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Accrued liabilities	$ 11,619	$ 5,348
Other non-current liabilities	$ 5,308	$ 8,943

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities - Impact of Interest Rate Swap (Details) - Interest Rate Swap - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Loss recognized in OCI	$ (2,288)	$ (6,280)	$ (7,777)
Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Loss reclassified from AOCI into income (effective portion)	$ (10,125)	$ (3,254)	$ (373)

Fair Value Measures - Carrying

Fair Value Measures - Carrying Amounts and Fair Values of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 15, 2020	Dec. 31, 2019
US ABL Facilities | Line of Credit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt issuance costs	$ 40,800		$ 17,800
Multicurrency Facility | Line of Credit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt issuance costs	0
2022 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt issuance costs			5,400
2023 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt issuance costs			7,200
2025 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt issuance costs	12,900	$ 14,300
2028 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt issuance costs	8,400
Canadian ABL Facility | Line of Credit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt issuance costs			0
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	2,392,456		1,632,589
Carrying Amount | US ABL Facilities | Line of Credit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	1,263,833		885,245
Carrying Amount | Multicurrency Facility | Line of Credit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Carrying Amount | 2022 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		264,576
Carrying Amount | 2023 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		482,768
Carrying Amount | 2025 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	637,068		0
Carrying Amount | 2028 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	491,555		0
Fair Value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	0		0
Fair Value | Level 1 | US ABL Facilities | Line of Credit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 1 | Multicurrency Facility | Line of Credit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 1 | 2022 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 1 | 2023 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 1 | 2025 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 1 | 2028 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	2,518,308		1,702,584
Fair Value | Level 2 | US ABL Facilities | Line of Credit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	1,304,612		903,000
Fair Value | Level 2 | Multicurrency Facility | Line of Credit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 2 | 2022 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		282,250
Fair Value | Level 2 | 2023 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		517,334
Fair Value | Level 2 | 2025 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	694,876		0
Fair Value | Level 2 | 2028 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	518,820		0
Fair Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	0		0
Fair Value | Level 3 | US ABL Facilities | Line of Credit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 3 | Multicurrency Facility | Line of Credit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 3 | 2022 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 3 | 2023 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 3 | 2025 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	0		0
Fair Value | Level 3 | 2028 Secured Notes | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	$ 0		$ 0

Fair Value Measures - Additiona

Fair Value Measures - Additional Information (Details) - Mobile Mini, Inc. $ in Thousands	Jul. 02, 2020shares	Jul. 01, 2020USD ($)yearshares
Business Acquisition [Line Items]
Number of shares exchanged (in shares)		2.405
Purchase price paid in stock (in shares)		106,426,721
Expected volatility
Business Acquisition [Line Items]
Purchase price paid in stock, measurement input		0.5192
Risk-free rate of interest
Business Acquisition [Line Items]
Purchase price paid in stock, measurement input		0.0017
Dividend Yield
Business Acquisition [Line Items]
Purchase price paid in stock, measurement input		0
Expected life
Business Acquisition [Line Items]
Purchase price paid in stock, measurement input | year		2
Stock Options
Business Acquisition [Line Items]
Number of shares exchanged (in shares)	2.405
Purchase price paid in stock (in shares)	7,361,516	7,361,516
Purchase price paid in stock | $		$ 19,279

Restructuring - Additional Info

Restructuring - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 6,527	$ 3,755	$ 15,468
NA Modular
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2,100
NA Storage
Restructuring Cost and Reserve [Line Items]
Restructuring costs	4,000
UK Storage
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 400

Restructuring - Summary of Acti

Restructuring - Summary of Activities in the Restructuring Accruals (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restructuring Reserve [Roll Forward]
Beginning balance	$ 447	$ 5,516	$ 227
Reclassification of liability to operating lease asset at the adoption of ASC 842	0	(972)	0
Charges	6,527	3,755	15,468
Cash payments	(5,356)	(5,694)	(10,120)
Foreign currency translation	30	(136)	(59)
Non-cash movements	102	(2,022)	0
Ending balance	1,750	447	5,516
Employee Costs
Restructuring Reserve [Roll Forward]
Beginning balance	447	4,544	227
Reclassification of liability to operating lease asset at the adoption of ASC 842	0	0	0
Charges	6,510	1,955	10,182
Cash payments	(5,356)	(5,694)	(5,806)
Foreign currency translation	30	(136)	(59)
Non-cash movements	119	(222)	0
Ending balance	1,750	447	4,544
Facility Exit Costs
Restructuring Reserve [Roll Forward]
Beginning balance	0	972	0
Reclassification of liability to operating lease asset at the adoption of ASC 842	0	(972)	0
Charges	17	1,800	5,286
Cash payments	0	0	(4,314)
Foreign currency translation	0	0	0
Non-cash movements	(17)	(1,800)	0
Ending balance	$ 0	$ 0	$ 972

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Award Activity (Details) - Restricted Stock Awards - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Awards
Beginning Balance (in shares)	52,755	72,053	0
Granted (in shares)	65,959	52,755	72,053
Vested (in shares)	(61,266)	(72,053)
Ending Balance (in shares)	57,448	52,755	72,053
Weighted-Average Grant Date Fair Value
Beginning Balance (in USD per share)	$ 14.69	$ 15.57	$ 0
Granted (in USD per share)	11.75	14.69	15.57
Vested (in USD per share)	14.28	15.57
Ending Balance (in USD per share)	$ 11.75	$ 14.69	$ 15.57

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details)	Jul. 02, 2020USD ($)shares	Jul. 01, 2020shares	Dec. 31, 2020USD ($)	Dec. 31, 2020USD ($)$ / shares	Dec. 31, 2019USD ($)$ / shares	Dec. 31, 2018USD ($)$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense				$ 9,879,000	$ 6,686,000	$ 3,439,000
Weighted-average grant date fair value (in USD per share) | $ / shares				$ 0	$ 0	$ 5.51
Options outstanding, intrinsic value			$ 22,200,000	$ 22,200,000
Options exercisable, intrinsic value			19,600,000	19,600,000
Options exercised, intrinsic value				30,700,000	$ 100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value				31,800,000	1,800,000	$ 0
Mobile Mini, Inc.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price paid in stock (in shares) | shares		106,426,721
Number of shares exchanged (in shares)		2.405
Stock Options | Mobile Mini, Inc.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price paid in stock (in shares) | shares	7,361,516	7,361,516
Number of shares exchanged (in shares)	2.405
Purchase price paid in stock	$ 19,300,000
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense			900,000		1,000,000	500,000
Unrecognized compensation expense for non-option awards			200,000	$ 200,000
Weighted average remaining vesting period				4 months 24 days
Time-Based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense				$ 5,600,000	3,900,000	2,300,000
Unrecognized compensation expense for non-option awards			13,300,000	$ 13,300,000
Weighted average remaining vesting period				2 years 8 months 12 days
Performance-Based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense				$ 2,500,000	1,000,000	0
Unrecognized compensation expense for non-option awards			5,400,000	$ 5,400,000
Weighted average remaining vesting period				1 year 9 months 18 days
WillScot Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense				$ 700,000	$ 800,000	$ 600,000
Weighted average remaining vesting period				1 year 2 months 12 days
Options vested, fair value				7 years 2 months 12 days
Unrecognized compensation expense for options			$ 900,000	$ 900,000
Converted Mobile Mini Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options vested, fair value				5 years 3 months 18 days

Stock-Based Compensation - Time

Stock-Based Compensation - Time-Based RSU Award Activity (Details) - Time-Based RSUs - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Awards
Beginning Balance (in shares)	1,065,305	852,733	0
Granted (in shares)	632,864	478,400	921,730
Forfeited (in shares)	(33,558)	(52,648)	(68,997)
Vested (in shares)	(538,845)	(213,180)
Ending Balance (in shares)	1,125,766	1,065,305	852,733
Weighted-Average Grant Date Fair Value
Beginning Balance (in USD per share)	$ 12.78	$ 13.60	$ 0
Granted (in USD per share)	14.37	11.69	13.60
Forfeited (in USD per share)	13.28	12.78	13.60
Vested (in USD per share)	13.24	12.78
Ending Balance (in USD per share)	$ 13.44	$ 12.78	$ 13.60

Stock-Based Compensation - Perf

Stock-Based Compensation - Performance-Based RSU Award Activity (Details) - Performance-Based RSUs - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Awards
Beginning Balance (in shares)	288,281	0
Granted (in shares)	325,256	302,182
Forfeited (in shares)	(12,700)	(13,901)
Vested (in shares)	(7,449)
Ending Balance (in shares)	593,388	288,281
Weighted-Average Grant Date Fair Value
Beginning Balance (in USD per share)	$ 13.22	$ 0
Granted (in USD per share)	16.35	13.22
Forfeited (in USD per share)	14.70	13.22
Vested (in USD per share)	16.82
Ending Balance (in USD per share)	$ 14.88	$ 13.22

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Option Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
WillScot Options
Options
Beginning balance (in shares)	534,188	589,257	0
Granted (in shares)	0		589,257
Forfeited (in shares)		41,302
Exercised (in shares)	0	13,767
Cancelled in settlement of taxes or Exercise Price (in shares)	0
Ending balance (in shares)	534,188	534,188	589,257
Weighted-Average Exercise Price per Share
Beginning balance (in USD per share)	$ 13.60	$ 13.60	$ 0
Granted (in USD per share)	0		13.60
Forfeited (in USD per share)		13.60
Exercised (in USD per share)	0	13.60
Cancelled in settlement of taxes or Exercise Price (in USD per share)	0
Ending balance (in USD per share)	$ 13.60	$ 13.60	$ 13.60
Vested and exercisable stock options (in shares)	267,094	133,547	0
Vested and exercisable stock options (in USD per share)	$ 13.60	$ 13.60	$ 0
Vested (in shares)	133,547	133,547
Vested (in USD per share)	$ 13.60	$ 13.60
Converted Mobile Mini Options
Options
Beginning balance (in shares)	0	0	0
Granted (in shares)	7,361,516		0
Forfeited (in shares)		0
Exercised (in shares)	428,653	0
Cancelled in settlement of taxes or Exercise Price (in shares)	(4,901,408)
Ending balance (in shares)	2,031,455	0	0
Weighted-Average Exercise Price per Share
Beginning balance (in USD per share)	$ 0	$ 0	$ 0
Granted (in USD per share)	13.52		0
Forfeited (in USD per share)		0
Exercised (in USD per share)	13.07	0
Cancelled in settlement of taxes or Exercise Price (in USD per share)	13.04
Ending balance (in USD per share)	$ 14.78	$ 0	$ 0
Vested and exercisable stock options (in shares)	2,031,455	0	0
Vested and exercisable stock options (in USD per share)	$ 14.78	$ 0	$ 0
Vested (in shares)	2,031,455	0
Vested (in USD per share)	$ 14.78	$ 0

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments for the acquisition of rental equipment and property, plant, and equipment	$ 5	$ 4.5

Segment Reporting - Narrative (

Segment Reporting - Narrative (Details)	12 Months Ended
	Dec. 31, 2020segment
Segment Reporting [Abstract]
Number of reportable segments	4

Segment Reporting - Segment Rep

Segment Reporting - Segment Reporting and Geographic Areas (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues:
Leasing									$ 1,001,447	$ 744,185
Leasing											$ 518,235
Total revenues	$ 437,647	$ 417,315	$ 256,862	$ 255,821	$ 278,045	$ 268,222	$ 263,713	$ 253,685	1,367,645	1,063,665	751,412
Costs:
Leasing									227,376	213,151	143,120
Depreciation of rental equipment									200,581	174,679	121,436
Gross profit	$ 234,255	$ 209,564	$ 109,964	$ 106,190	$ 109,191	$ 99,307	$ 101,484	$ 103,331	659,973	413,313	289,384
Other selected data:
Adjusted EBITDA									530,307	356,548	215,533
Selling, general and administrative expense									424,679	271,004	254,871
Purchases of rental equipment and refurbishments									172,383	205,106	160,883
Delivery and installation
Revenues:
Revenues									274,156	220,057	154,557
Costs:
Cost of sales									220,102	194,107	143,950
New units
Revenues:
Revenues									53,093	59,085	53,603
Total revenues									53,093	59,085	53,603
Costs:
Cost of sales									34,841	42,160	36,863
Rental units
Revenues:
Revenues									38,949	40,338	25,017
Total revenues									38,949	40,338	25,017
Costs:
Cost of sales									24,772	26,255	16,659
Unallocated Costs
Other selected data:
Adjusted EBITDA									0	0	0
Selling, general and administrative expense									91,864	35,776	53,976
Purchases of rental equipment and refurbishments									0	0	0
NA Modular | Operating Segments
Revenues:
Leasing									770,330	744,185
Leasing											518,235
Total revenues									1,051,162	1,063,665	751,412
Costs:
Leasing									194,442	213,151	143,120
Depreciation of rental equipment									182,605	174,679	121,436
Gross profit									451,642	413,313	289,384
Other selected data:
Adjusted EBITDA									394,805	356,548	215,533
Selling, general and administrative expense									242,010	235,228	200,895
Purchases of rental equipment and refurbishments									153,327	205,106	160,883
NA Modular | Operating Segments | Delivery and installation
Revenues:
Revenues									208,079	220,057	154,557
Costs:
Cost of sales									175,705	194,107	143,950
NA Modular | Operating Segments | New units
Revenues:
Revenues									41,858	59,085	53,603
Costs:
Cost of sales									27,555	42,160	36,863
NA Modular | Operating Segments | Rental units
Revenues:
Revenues									30,895	40,338	25,017
Costs:
Cost of sales									19,213	26,255	16,659
NA Storage | Operating Segments
Revenues:
Leasing									166,128	0
Leasing											0
Total revenues									221,829	0	0
Costs:
Leasing									19,925	0	0
Depreciation of rental equipment									9,585	0	0
Gross profit									156,785	0	0
Other selected data:
Adjusted EBITDA									99,837	0	0
Selling, general and administrative expense									66,533	0	0
Purchases of rental equipment and refurbishments									14,969	0	0
NA Storage | Operating Segments | Delivery and installation
Revenues:
Revenues									42,655	0	0
Costs:
Cost of sales									27,029	0	0
NA Storage | Operating Segments | New units
Revenues:
Revenues									6,976	0	0
Costs:
Cost of sales									4,244	0	0
NA Storage | Operating Segments | Rental units
Revenues:
Revenues									6,070	0	0
Costs:
Cost of sales									4,261	0	0
UK Storage | Operating Segments
Revenues:
Leasing									32,633	0
Leasing											0
Total revenues									46,361	0	0
Costs:
Leasing									7,391	0	0
Depreciation of rental equipment									1,648	0	0
Gross profit									27,642	0	0
Other selected data:
Adjusted EBITDA									17,822	0	0
Selling, general and administrative expense									11,468	0	0
Purchases of rental equipment and refurbishments									1,693	0	0
UK Storage | Operating Segments | Delivery and installation
Revenues:
Revenues									9,409	0	0
Costs:
Cost of sales									6,353	0	0
UK Storage | Operating Segments | New units
Revenues:
Revenues									3,124	0	0
Costs:
Cost of sales									2,301	0	0
UK Storage | Operating Segments | Rental units
Revenues:
Revenues									1,195	0	0
Costs:
Cost of sales									1,026	0	0
Tank and Pump | Operating Segments
Revenues:
Leasing									32,356	0
Leasing											0
Total revenues									48,293	0	0
Costs:
Leasing									5,618	0	0
Depreciation of rental equipment									6,743	0	0
Gross profit									23,904	0	0
Other selected data:
Adjusted EBITDA									17,843	0	0
Selling, general and administrative expense									12,804	0	0
Purchases of rental equipment and refurbishments									2,394	0	0
Tank and Pump | Operating Segments | Delivery and installation
Revenues:
Revenues									14,013	0	0
Costs:
Cost of sales									11,015	0	0
Tank and Pump | Operating Segments | New units
Revenues:
Revenues									1,135	0	0
Costs:
Cost of sales									741	0	0
Tank and Pump | Operating Segments | Rental units
Revenues:
Revenues									789	0	0
Costs:
Cost of sales									$ 272	$ 0	$ 0

Segment Reporting - Reconciliat

Segment Reporting - Reconciliation of Adjusted EBITDA (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting [Abstract]
Net income (loss) attributable to WillScot Mobile Mini common shareholders	$ 70,666	$ (11,122)	$ (51,175)
Net income (loss) attributable to non-controlling interest, net of tax	1,213	(421)	(4,532)
Non-cash deemed dividend related to warrant exchange	0	0	2,135
Loss on extinguishment of debt	42,401	8,755	0
Income tax benefit	(51,451)	(2,191)	(38,600)
Interest expense	119,886	122,504	98,433
Depreciation and amortization	243,830	187,074	134,740
Currency (gains) losses, net	(355)	(688)	2,454
Goodwill and other impairment charges	0	2,848	1,600
Restructuring costs, lease impairment expense and other related charges	11,403	12,429	15,468
Transaction costs	64,053	0	20,051
Integration costs	18,338	26,607	30,006
Stock compensation expense	9,879	6,686	3,439
Other	444	4,067	1,514
Adjusted EBITDA	$ 530,307	$ 356,548	$ 215,533

Segment Reporting - Assets Rela

Segment Reporting - Assets Related to Reportable Segments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Goodwill	$ 1,171,219	$ 235,177	$ 247,017
Intangible assets, net	495,947	126,625
NA Modular
Segment Reporting Information [Line Items]
Goodwill	235,828	235,177
Intangible assets, net	125,625	126,625
NA Storage
Segment Reporting Information [Line Items]
Goodwill	726,529	0
Intangible assets, net	329,437	0
UK Storage
Segment Reporting Information [Line Items]
Goodwill	65,600	0
Intangible assets, net	11,177	0
Tank and Pump
Segment Reporting Information [Line Items]
Goodwill	143,262	0
Intangible assets, net	29,708	0
Total rental equipment
Segment Reporting Information [Line Items]
Property, plant and equipment, net	2,933,722	1,944,436
Total rental equipment | NA Modular
Segment Reporting Information [Line Items]
Property, plant and equipment, net	1,888,287	1,944,436
Total rental equipment | NA Storage
Segment Reporting Information [Line Items]
Property, plant and equipment, net	772,356	0
Total rental equipment | UK Storage
Segment Reporting Information [Line Items]
Property, plant and equipment, net	147,720	0
Total rental equipment | Tank and Pump
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 125,359	$ 0

Related Parties - Related Party

Related Parties - Related Party Balances Included in Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Total related party liabilities, net	$ (431)	$ (210)
Trade receivables, net of allowances for credit losses
Related Party Transaction [Line Items]
Receivables due from affiliates	30	26
Accrued liabilities
Related Party Transaction [Line Items]
Amounts due to affiliates	$ (461)	$ (236)

Related Parties - Related Par_2

Related Parties - Related Party Transactions in Statement of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Leasing revenue from related parties	$ 1,066	$ 316
Leasing revenue from related parties			$ 720
Consulting expense to related party	(5,194)	(1,029)	(3,070)
Total related party expense, net	(3,748)	(713)	(802)
Rental units
Related Party Transaction [Line Items]
Rental unit sales to related parties	$ 380	$ 0	$ 1,548

Related Parties - Narrative (De

Related Parties - Narrative (Details) - USD ($)	Jun. 30, 2020	Aug. 24, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Aug. 22, 2018
Related Party Transaction [Line Items]
Shares issued for conversion (in shares)	10,641,182
Majority Shareholder
Related Party Transaction [Line Items]
Term of agreement		2 years
Number of shares pledged for collateral (in shares)			59,725,558
Majority Shareholder | Private Placement Warrants
Related Party Transaction [Line Items]
Number of warrants pledged for collateral (in shares)			4,850,000
Affiliates
Related Party Transaction [Line Items]
Purchases from affiliates			$ 3,100,000	$ 4,700,000	$ 4,300,000
Sapphire Holding
Related Party Transaction [Line Items]
Percentage ownership			26.10%
Margin Loan | Sapphire Holding
Related Party Transaction [Line Items]
Debt, face amount						$ 125,000,000

Quarterly Financial Data - Summ

Quarterly Financial Data - Summary of Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Total revenue	$ 437,647	$ 417,315	$ 256,862	$ 255,821	$ 278,045	$ 268,222	$ 263,713	$ 253,685	$ 1,367,645	$ 1,063,665	$ 751,412
Gross profit	234,255	209,564	109,964	106,190	109,191	99,307	101,484	103,331	659,973	413,313	289,384
Operating income (loss)	91,263	25,012	41,067	25,373	39,986	29,781	26,294	21,464	182,715	117,525	6,261
Net (loss) income	46,468	16,252	12,833	(3,674)	8,928	996	(11,438)	(10,029)	71,879	(11,543)	(53,572)
Net income (loss) attributable to WillScot Mobile Mini	$ 46,468	$ 16,252	$ 11,490	$ (3,544)	$ 8,054	$ 701	$ (10,606)	$ (9,271)	$ 70,666	$ (11,122)	$ (49,040)
(Loss) earnings per share - basic (in USD per share)	$ 0.20	$ 0.07	$ 0.10	$ (0.03)	$ 0.07	$ 0.01	$ (0.10)	$ (0.09)	$ 0.42	$ (0.10)	$ (0.59)
(Loss) earnings per share - diluted (in USD per share)	$ 0.20	$ 0.07	$ 0.10	$ (0.03)	$ 0.07	$ 0.01	$ (0.10)	$ (0.09)	$ 0.41	$ (0.10)	$ (0.59)
Weighted average shares - basic (in shares)	228,637,826	226,649,993	110,692,426	109,656,646	108,793,847	108,720,857	108,693,924	108,523,269	169,230,177	108,683,820	87,209,605
Weighted average shares - diluted (in shares)	236,696,853	231,216,573	111,432,963	109,656,646	114,080,059	112,043,866	108,693,924	108,523,269	173,650,251	108,683,820	87,209,605
Total leasing and services revenue
Disaggregation of Revenue [Line Items]
Total revenue	$ 409,622	$ 384,776	$ 241,783	$ 239,422	$ 245,755	$ 249,411	$ 241,784	$ 227,292	$ 1,275,603	$ 964,242	$ 672,792

Earnings (Loss) Per Share - Nar

Earnings (Loss) Per Share - Narrative (Details) - shares	Jun. 30, 2020	Jan. 19, 2018	Nov. 29, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issued for conversion (in shares)	10,641,182
Performance-Based RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Minimum payout percentage				0.00%		0.00%
Maximum payout percentage				150.00%		150.00%
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of diluted earnings per share because their effect would have been anti-dilutive (in shares)				534,188	589,257
Time-Based RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of diluted earnings per share because their effect would have been anti-dilutive (in shares)				1,065,305	852,733
Performance-Based RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of diluted earnings per share because their effect would have been anti-dilutive (in shares)				288,281
RSAs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of diluted earnings per share because their effect would have been anti-dilutive (in shares)				52,755	72,053
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of diluted earnings per share because their effect would have been anti-dilutive (in shares)				22,093,950	22,183,513
Class A Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Converted shares held in escrow (in shares)			12,425,000
Shares released from escrow (in shares)		6,212,500

Earnings (Loss) Per Share - Rec

Earnings (Loss) Per Share - Reconciliation of Weighted Average Shares Outstanding (Details) - shares	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Basic (in shares)	228,637,826	226,649,993	110,692,426	109,656,646	108,793,847	108,720,857	108,693,924	108,523,269	169,230,177	108,683,820	87,209,605
Warrants (in shares)									3,116,000
Diluted (in shares)	236,696,853	231,216,573	111,432,963	109,656,646	114,080,059	112,043,866	108,693,924	108,523,269	173,650,251	108,683,820	87,209,605
RSAs
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Awards (in shares)									33,000
Time-Based RSUs
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Awards (in shares)									315,000
Performance-Based and Market-Based RSUs
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Awards (in shares)									322,000
Stock Options
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Awards (in shares)									634,000