Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net loss	$ (22,858)	$ (59,796)	$ (60,501)	$ (180,756)
Change in fair value of derivative instruments, accounted for as hedges, net of income tax benefit of $475, $2,046, $561 and $1,099, respectively	(1,275)	(3,454)	(1,420)	(1,856)
Comprehensive loss	$ (24,133)	$ (63,250)	$ (61,921)	$ (182,612)