Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Statement of Other Comprehensive Income [Abstract]
Net income (loss)	$ 1,670	$ (37,354)	$ 10,506	$ (107,912)
Change in fair value of derivative instruments, accounted for as hedges, net of income tax expense (benefit) of $(46), $1,435, $485 and $2,032, respectively.	(78)	(2,423)	819	(3,431)
Comprehensive income (loss)	$ 1,592	$ (39,777)	$ 11,325	$ (111,343)