Lease Incentives (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Lease Incentives
Non-contingent lease incentives	$ 2,652		$ 2,652		$ 14,443
Non-contingent lease incentives, funding			283	$ 1,017
Total funding			283	1,017
Non-contingent lease incentives, Amortization			(181)	(852)
Contingent lease incentives, Amortization				(239)
Total amortization	$ (94)	$ (551)	(181)	$ (1,091)
Non-contingent lease incentives, Adjustment			(11,893)
Total Adjustment			(11,893)
Contingent lease incentives, Write off					$ 12,093
Reclassification of Notes Receivable to Lease Incentives			$ 200