Net Income (Loss) Per Share - Computation of Basic and Diluted Net Income (Loss) per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Numerator:
Net income (loss) attributable to common stockholders	$ 91,687	$ (28,246)	$ (70,852)
Less: Deemed dividend to convertible preferred stockholders		(24,890)
Net income (loss) available to common stockholders	$ 91,687	$ (53,136)	$ (70,852)
Denominator:
Weighted average shares used to compute net income (loss) per share attributable to common stockholders, basic	102,367	55,091	22,795
Weighted average effect of potentially dilutive shares to purchase common stock	2,597
Weighted average shares used to compute net income (loss) per share attributable to common stockholders, diluted	104,964	55,091	22,795
Net income (loss) per share attributable to common stockholders
Basic	$ 0.90	$ (0.96)	$ (3.11)
Diluted	$ 0.87	$ (0.96)	$ (3.11)