Revenue Recognition - Schedule of Significant Changes in Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Contractors [Abstract]
Contract assets	$ 0	$ 987
Change in Contract Asset	$ (987)
Percent Change in Contract Asset	(100.00%)
Contract liabilities	$ (101)	0
Change in Contract Liability	$ (101)
Percent Change in Contract Liability	0.00%
Net contract assets (liabilities)	$ (101)	$ 987
Change in Net Contract Assets (Liabilities)	$ (1,088)
Percent Change in Net Contract Assets (Liabilities)	(110.20%)