Accounts Receivable - Allowance (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	$ 429	$ 392	$ 353	$ 264
Provisions (recoveries) for expected credit losses, net of adjustments	117	(37)	193	91
Accounts receivable written off, net of recoveries	0	(2)	0	(2)
Balance, end of period	$ 546	$ 353	$ 546	$ 353