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	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Numerator:
Net income (loss) attributable to common stockholders	$ 16,878	$ (2,768)	$ 62,655	$ (13,223)
Less: Deemed dividend to convertible preferred stockholders		(24,890)		(24,890)
Net income (loss) available to common stockholders	$ 16,878	$ (27,658)	$ 62,655	$ (38,113)
Denominator:
Weighted average shares used to compute net income (loss) per share attributable to common stockholders, basic	102,707	67,732	101,988	39,612
Weighted average effect of potentially dilutive shares to purchase common stock	2,385		2,710
Weighted average shares used to compute net income (loss) per share attributable to common stockholders, diluted	105,092	67,732	104,698	39,612
Net income (loss) per share attributable to common stockholders
Basic	$ 0.16	$ (0.41)	$ 0.61	$ (0.96)
Diluted	$ 0.16	$ (0.41)	$ 0.60	$ (0.96)