Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Components of the provision for income taxes
Federal	$ 0	$ 0	$ 0	$ 0
State	24	(8,308)	265	2,092
Deferred portion of income tax expense (benefit)	(23,756)	4,168	(314,770)	(80,388)
Total income tax expense (benefit)	$ (23,732)	$ (4,140)	$ (314,505)	$ (78,296)
Effective tax rate	36.70%	403.50%	36.10%	42.20%