Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets
Cash	$ 2,329	$ 1,238
Accounts receivable, net of allowance for doubtful accounts of $2,100 in 2021 and 2020	122,208	123,316
Rental equipment, at cost:
Relocatable modular buildings	886,299	882,115
Electronic test equipment	342,105	333,020
Liquid and solid containment tanks and boxes	314,444	315,706
Rental equipment, gross	1,542,848	1,530,841
Less accumulated depreciation	(606,905)	(592,725)
Rental equipment, net	935,943	938,116
Property, plant and equipment, net	135,034	136,210
Prepaid expenses and other assets	41,643	41,549
Intangible assets, net	7,069	7,118
Goodwill	28,197	28,197
Total assets	1,272,423	1,275,744
Liabilities:
Notes payable	208,806	222,754
Accounts payable and accrued liabilities	112,551	108,334
Deferred income	50,562	45,975
Deferred income taxes, net	212,819	216,077
Total liabilities	584,738	593,140
Shareholders’ equity:
Common stock, no par value - Authorized 40,000 shares Issued and outstanding - 24,206 shares as of March 31, 2021 and 24,128 shares as of December 31, 2020	104,584	106,289
Retained earnings	583,167	576,419
Accumulated other comprehensive loss	(66)	(104)
Total shareholders’ equity	687,685	682,604
Total liabilities and shareholders’ equity	$ 1,272,423	$ 1,275,744