Schedule II - Valuation and Qualifying Accounts - Allowance for Credit Losses (Details) - Allowance for credit losses deducted from financing receivables in the balance sheet - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 1,489	$ 2,971	$ 2,567
Additions charged to cost and expenses	481	1,632	970
Deductions	(1,248)	(3,114)	(566)
Balance at end of period	$ 722	$ 1,489	$ 2,971