Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Basic EPS
Net income (loss)	$ (14,219)	$ 3,466	$ (64,185)	$ (76,846)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ (14,219)	$ 3,466	$ (64,185)	$ (76,846)
Weighted average shares
Basic (in shares)	135,247,000	102,470,000	124,478,000	102,427,000
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	0	91,000	0	0
Diluted (in shares)	135,247,000	102,561,000	124,478,000	102,427,000
Income (loss) per share
Basic	$ (0.11)	$ 0.03	$ (0.52)	$ (0.75)
Diluted	$ (0.11)	$ 0.03	$ (0.52)	$ (0.75)
Convertible Senior Notes Due March 2028 [Member]
Earnings Per Share (Textual) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	3.25%		3.25%		3.25%
Stock Options [Member]
Earnings Per Share (Textual) [Abstract]
Number of shares of common stock equivalents related to convertible debt	3,302,701	1,387,957	3,251,347	2,008,749
Operating Segments [Member]
Basic EPS
Net income (loss)	$ (14,219)	$ 3,466		$ (76,846)