Accounts Receivable and Contract Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Accounts Receivable and Contract Assets [Abstract]
Accounts receivable - customers	$ 4,574	$ 4,731
Other receivables	152	385
Accounts receivable	4,726	5,116
Less: allowance for doubtful accounts	(305)	(305)
Accounts receivable, net	4,421	4,811
Unbilled revenue	2,276	$ 2,427
Change in accounts receivable - customers	(157)
Change in other receivables	(233)
Change in accounts receivable	(390)
Change in allowance for doubtful accounts	0
Change in accounts receivable, net	(390)
Change in unbilled revenue	$ (151)