Net Income (Loss) Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended				3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014 Convertible Senior Notes Due March 2028 [Member]	Dec. 31, 2013 Convertible Senior Notes Due March 2028 [Member]	Jun. 30, 2014 Stock Options [Member]	Jun. 30, 2013 Stock Options [Member]	Jun. 30, 2014 Stock Options [Member]	Jun. 30, 2013 Stock Options [Member]
Earnings Per Share (Textual) [Abstract]
Number of shares of common stock equivalents related to convertible debt							2,147,989	1,202,100	2,147,390	1,202,100
Debt Instrument, Interest Rate, Stated Percentage					3.25%	3.25%
Basic EPS
Net income (loss) available to common stockholders	$ (43,121)	$ (35,040)	$ (80,312)	$ (22,770)
Weighted average shares
Basic (in shares)	102,444,000	99,833,000	102,405,000	94,918,000
Effect of share based compensation plans (in shares)	0	0	0	0
Diluted (in shares)	102,444,000	99,833,000	102,405,000	94,918,000
Income (loss) per share
Basic (in dollars per share)	$ (0.42)	$ (0.35)	$ (0.78)	$ (0.24)
Diluted (in dollars per share)	$ (0.42)	$ (0.35)	$ (0.78)	$ (0.24)