Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Tax Disclosure [Abstract]
(Loss) income before provision for income taxes	$ (55,860)	$ 31,234	$ (34,348)	$ 25,180
Income tax (benefit) expense using estimated annual effective income tax rate	(22,763)	12,024	(13,997)	9,694
Changes in effective tax rates	1,181	1,426	1,159	1,400
Out-of-period adjustment related to non-deductible expenses in 2011	0	0	0	757
Increase in unrecognized tax benefits	251	0	373	0
Impact of discrete items associated with debt retirement	0	(148)	816	(808)
Impact of discrete item associated with litigation settlement	2,362	0	2,362	0
Income tax (benefit) expense	$ (18,969)	$ 13,302	$ (9,287)	$ 11,043