Earnings Per Share - Reconciliation of Numerators and Denominators of Basic and Diluted Earnings Per Computations (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Numerator / net income
Income (loss) from continuing operations and shares used in basic calculations	$ 249,104	$ 62,434	$ 126,092
Denominator / shares
Income from continuing operations and shares used in basic calculations (in shares)	100,437	112,854	80,143
Income from continuing operations and shares used in diluted calculations (in shares)	102,922	116,534	81,015
Loss from continuing operations allocated to preferred and participating units	$ 0	$ 0	$ (21,565)
Income from continuing operations attributable to common stockholders	$ 249,104	$ 62,434	$ 147,657
Basic earnings per common share from continuing operations (in dollars per share)	$ 2.48	$ 0.55	$ 1.84
Diluted earnings per common share from continuing operations (in dollars per share)	$ 2.42	$ 0.54	$ 1.82
Restricted awards
Denominator / shares
Effect of dilutive stock based awards (in shares)	1,955	3,579	855
Stock options and SARs
Denominator / shares
Effect of dilutive stock based awards (in shares)	316	101	17
Warrants
Denominator / shares
Effect of dilutive stock based awards (in shares)	214	0	0