Net Income (Loss) Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Numerator:
Net income (loss)	$ (70,816)	$ (24,843)	$ (50,722)	$ (62,384)
Basic net income (loss) allocable to common shareholders	(70,816)	(24,843)	(50,722)	(62,384)
Diluted net income (loss) allocable to common shareholders	$ (70,816)	$ (24,843)	$ (50,722)	$ (62,384)
Weighted average number of shares used to compute net income (loss) per share:
Basic (in shares)	376,563,000	370,720,000	375,927,000	369,973,000
Diluted (in shares)	376,563,000	370,720,000	375,927,000	369,973,000
Net income (loss) per share:
Basic (in dollars per share)	$ (0.19)	$ (0.07)	$ (0.13)	$ (0.17)
Diluted (in dollars per share)	$ (0.19)	$ (0.07)	$ (0.13)	$ (0.17)
Outstanding restricted stock awards and restricted stock units excluded from the computations of diluted net income (loss) per share (in shares)	14,200,000	16,900,000	14,200,000	16,900,000