Net Income (Loss) per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Numerator:
Net income (loss) - basic	$ (33,671)	$ (56,212)
Net income (loss) - diluted	$ (33,671)	$ (56,212)
Denominator:
Weighted average common shares outstanding - basic	71,087	63,697
Weighted-average common shares outstanding and dilutive potential common shares - diluted	71,087	63,697
Net income (loss) per share:
Basic (in dollars per share)	$ (0.47)	$ (0.88)
Diluted (in dollars per share)	$ (0.47)	$ (0.88)