Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Basic EPS
Net income (loss)	$ (367,183)	$ (1,186,874)	$ (650,563)
Weighted average shares
Basic (in shares)	129,639,000	102,441,000	97,864,000
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	0	0	0
Diluted (in shares)	129,639,000	102,441,000	97,864,000
Income (loss) per share
Basic (in dollars per share)	$ (2.83)	$ (11.59)	$ (6.65)
Diluted (in dollars per share)	$ (2.83)	$ (11.59)	$ (6.65)
Convertible Senior Notes Due March 2028 [Member]
Earnings Per Share (Textual) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	3.25%	3.25%
Stock Options [Member]
Earnings Per Share (Textual) [Abstract]
Number of shares of common stock equivalents related to convertible debt	3,239,425	1,871,681	1,111,021
Operating Segments [Member]
Basic EPS
Net income (loss)		$ (1,186,874)	$ (650,563)