Accounts Receivable (Allowance) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Allowance for credit losses:
Balance, beginning of period	$ 506	$ 353	$ 264
Provision for credit losses on accounts receivable, net of adjustments	43	153	91
Accounts receivable written off, net of recoveries	0	0	(2)
Balance, end of period	$ 549	$ 506	$ 353