Earnings Per Share (Summary Of Basic And Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Net income (loss) attributable to common stockholders	$ (73,942)	$ (27,776)	$ 9,690	$ (5,979)	$ (56,867)	$ 12,009	$ 19,523	$ 6,373	$ (98,007)	$ (18,962)	$ 10,420
Less: adjustment for income allocated to participating securities											(36)
Net income (loss) attributable to common stockholders - basic and diluted									$ (98,007)	$ (18,962)	$ 10,384
Weighted average common shares outstanding - basic									75,604,000	85,140,000	87,989,000
Plus: dilutive effect of stock options and unvested restricted stock units											1,100,000
Weighted average common shares outstanding - diluted									75,604,000	85,140,000	89,089,000
Basic	$ (1.01)	$ (0.37)	$ 0.11	$ (0.08)	$ (0.70)	$ 0.12	$ 0.19	$ 0.06	$ (1.30)	$ (0.22)	$ 0.12
Diluted	$ (1.01)	$ (0.37)	$ 0.11	$ (0.08)	$ (0.70)	$ 0.12	$ 0.19	$ 0.06	$ (1.30)	$ (0.22)	$ 0.12
Anti-dilutive options and RSUs not included in the calculation of diluted income (loss) per share									2,100,000	2,000,000	1,000,000
Percentage of common stock if-converted Series A preferred stock									15.90%
Anti-dilutive Series A preferred shares not included in the calculation of EPS									13,793,100