Income Taxes (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current income tax (benefit) provision
Federal income tax	$ (455)	$ (8,178)	$ (1,144)
State income tax	0	21	108
Net current income tax benefit	(455)	(8,157)	(1,036)
Deferred income tax (benefit) provision
Federal income tax	(20,457)	0	0
State income tax	13,221	0	0
Net deferred income tax benefit	(7,236)	0	0
Deferred income tax provision (benefit)
Federal tax (benefit) expense at statutory rate	61,543	45,447	(34,333)
State income tax	16,181	368	539
Permanent differences	(2,488)	(4,740)	(499)
AMT credit refundable	0	0	1,144
AMT credit refundable	455	8,178	0
Tax Cuts and Jobs Act rate change	0	51,525	0
Change in federal valuation allowance	(80,003)	(101,917)	33,688
Change in state valuation allowance	(2,924)	1,139	(539)
Net deferred income tax benefit	(7,236)	0	0
Net current income tax benefit	(455)	(8,157)	(1,036)
Total income tax benefit	$ (7,691)	$ (8,157)	$ (1,036)