Net Income (Loss) Per Common Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Net Income (Loss) Per Common Share
Number of outstanding options not included in computation of Diluted EPS (in shares)	2,945,000	3,437,000
Numerator
Net Income (Loss)	$ (22,887)	$ 3,233
Denominator
Weighted average number of common shares outstanding	51,467,000	51,763,000
Effect of outstanding share-based awards (in shares)		734,000
Weighted average number of shares for diluted earnings (loss) per common share	51,467,000	52,497,000
Basic earnings (loss) per share (in dollars per share)	$ (0.44)	$ 0.06
Diluted earnings (loss) per share (in dollars per share)	$ (0.44)	$ 0.06