Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Numerator:
Net loss	$ (28,841)	$ (58,993)
Basic net loss allocable to common shareholders	(28,841)	(58,993)
Diluted net loss allocable to common shareholders	$ (28,841)	$ (58,993)
Weighted average number of shares used to compute net income (loss) per share:
Basic (in shares)	387,312	384,435
Diluted (in shares)	387,312	384,435
Net income (loss) per share:
Basic (in dollars per share)	$ (0.07)	$ (0.15)
Diluted (in dollars per share)	$ (0.07)	$ (0.15)
Outstanding restricted stock awards and units excluded from the computations of diluted net income per share (in shares)	14,600	13,600

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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