CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Current assets
Accounts receivable, allowance for doubtful accounts	$ 400	$ 393
Rental equipment net of accumulated depreciation	1,808,001	1,781,321
Rental equipment, accumulated depreciation	691,842	669,360
Net investment in direct finance leases	585,016	550,573
Current liabilities
Current portion of debt	183,878	183,448
Debt	$ 1,642,879	$ 1,562,283
Stockholders' equity
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	84,000,000	84,000,000
Common stock, shares issued	17,304,111	17,562,779
Common stock, shares outstanding	17,304,111	17,562,779
Variable Interest Entity, Primary Beneficiary [Member]
Current assets
Cash	$ 23,942	$ 26,856
Rental equipment net of accumulated depreciation	73,212	77,907
Net investment in direct finance leases	2,150	2,683
Current liabilities
Current portion of debt	43,392	41,344
Debt	$ 48,120	$ 59,519
Series A Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Stock [Member]
Stockholders' equity
Preferred stock, dividend rate	8.50%	8.50%
Preferred stock, shares issued	2,199,610	2,199,610
Preferred stock, shares outstanding	2,199,610	2,199,610
Series B Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Stock [Member]
Stockholders' equity
Preferred stock, dividend rate	8.50%	8.50%
Preferred stock, shares issued	1,955,000	1,955,000
Preferred stock, shares outstanding	1,955,000	1,955,000