Basic and Diluted Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jun. 30, 2018
Numerator:
Net income (loss) attributable to common stockholders	$ (15,473)	$ 5,914
Denominator:
Weighted-average shares used to compute net income (loss) per share attributable to common stockholders, basic	65,569	61,926
Effect of dilutive securities:
Convertible senior notes	0	2,002
Contingently issuable shares (in shares)	0	11
Employee stock awards (in shares)	0	3,539
Weighted-average shares used to compute net income (loss) per share attributable to common stockholders, diluted	65,569	67,478
Net income (loss) per share attributable to common stockholders, basic (in dollars per share)	$ (0.24)	$ 0.10
Net income (loss) per share attributable to common stockholders, diluted (in dollars per share)	$ (0.24)	$ 0.09
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from calculation of earnings per share (in shares)	10,283	203
Stock awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from calculation of earnings per share (in shares)	4,146	203
Convertible senior notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from calculation of earnings per share (in shares)	6,137	0
Convertible Senior Notes | Convertible Senior Note due 2023, 0.5%
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Initial Conversion Price	$ 44.33		$ 44.33
Convertible Senior Notes | Convertible Senior Notes due 2024 & 2026, 0.50%, 1.0%
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Initial Conversion Price	$ 189.36