Earnings Per Share Basic and Diluted EPS (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Income from continuing operations, net of tax									$ 52,551	$ 119,493	$ 78,669
(Loss)/income from discontinued operations, net of tax	(91)	0	(24)	(3)	1	(10)	0	0	(118)	(9)	2,591
Net income									52,433	119,484	81,260
Series A-1 Preferred Stock dividend									4,375	0	0
Net income available to common stockholders									$ 48,058	$ 119,484	$ 81,260
Weighted average number of shares outstanding, Basic									42,693	39,912	38,886
Dilutive effect of employee stock-based awards									601	603	475
Dilutive effect of Series A-1 Preferred Stock									5,984	0	0
Weighted average shares - Diluted									51,316	42,772	41,889
Basic [Abstract]
Basic earnings per common share from continuing operations									$ 1.13	$ 2.99	$ 2.02
Basic (loss)/earnings per common share from discontinued operations									$ 0.00	$ 0.00	$ 0.07
Basic earnings per common share									$ 1.13	$ 2.99	$ 2.09
Diluted [Abstract]
Diluted earnings per common share from continuing operations	$ 0.18	$ (0.47)	$ 0.84	$ 0.52	$ 0.77	$ 0.77	$ 0.73	$ 0.52	$ 1.02	$ 2.79	$ 1.88
Diluted (loss)/earnings per common share from discontinued operations	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.06
Diluted earnings per common share	$ 0.18	$ (0.47)	$ 0.84	$ 0.52	$ 0.77	$ 0.77	$ 0.73	$ 0.52	$ 1.02	$ 2.79	$ 1.94
Class B [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Weighted average number of shares outstanding, Basic									2,038	2,257	2,528