Revenue, Contract Balances (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Revenue [Abstract]
Revenue recognized	$ 500
Contract liabilities [Abstract]
Unbilled receivables, current	296	$ 290
Unbilled receivables, non-current	441	591
Customer pre-payments	(87)	(216)
Deferred revenue, current	(742)	(504)
Deferred revenue, non-current	(232)	(111)
Contract with Customer, Asset (Liability), net	$ (324)	$ 50