Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Income from continuing operations		$ 49,446	$ 124,677	$ 222,688
Loss from discontinued operations, net of tax		(5,109)	(18,059)	(47,896)
Net income		44,337	106,618	174,792
Dividends and undistributed income allocated to participating shares		(1,329)	(3,929)	(5,473)
Income from continuing operations to common shares - basic		48,117	120,748	217,215
Effect of reallocating undistributed income from continuing operations to participating shares		1	58	179
Income from continuing operations to common shares - diluted		$ 48,118	$ 120,806	$ 217,394
Weighted average common shares - basic (in shares)		17,467	20,192	27,216
Dilutive effect of share-based payment awards (in shares)		20	81	235
Dilutive effect of convertible debt (in shares)		0	230	718
Weighted average shares used for diluted EPS (in shares)	[1]	17,487	20,503	28,169
Basic earnings (loss) per common share:
Continuing operations (in usd per share)		$ 2.75	$ 5.98	$ 7.98
Discontinued operations (in usd per share)		(0.29)	(0.89)	(1.76)
Basic earnings per share (in usd per share)		2.46	5.09	6.22
Diluted earnings (loss) per common share:
Continuing operations (in usd per share)		2.75	5.89	7.72
Discontinued operations (in usd per share)		(0.29)	(0.88)	(1.70)
Diluted earnings per share (in usd per share)		$ 2.46	$ 5.01	$ 6.02
Stock options and share-based awards not included in diluted EPS calculation because their effect would be antidilutive		7	11	13

[1] Participating securities were included in the calculation of diluted earnings per share using the two-class method, as this calculation was more dilutive than the calculation using the treasury stock method.