Convertible Senior Notes and Capped Call Transactions - Narrative (Details) $ / shares in Units, shares in Thousands, $ in Thousands		1 Months Ended	12 Months Ended
	Dec. 31, 2020 USD ($) Day $ / shares shares	Mar. 31, 2019 USD ($) Day $ / shares shares	Dec. 31, 2021 USD ($) $ / shares	Dec. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Common stock, par value (in dollars per share) | $ / shares	$ 0.001		$ 0.001	$ 0.001
Adjustments to additional paid in capital related to issuance costs attributable to equity component				$ (3,797)	$ (1,986)
Number of shares of common stock covered by called caps (shares) | shares	6,880	5,960
Reduction to additional paid-in-capital related to called caps	$ 46,100			(46,058)	(23,184)
Total interest expense			$ 37,533	$ 14,629	$ 9,999
2024 Notes
Debt Instrument [Line Items]
Reduction to additional paid-in-capital related to called caps		$ 23,200
Capped calls
Debt Instrument [Line Items]
Capped caps initial strike price (in dollars per share) | $ / shares	$ 75.23	$ 38.58		$ 75.23
Capped caps initial cap price (in dollars per share) | $ / shares	$ 105.58	$ 57.16		$ 105.58
Convertible Debt | 2024 Notes
Debt Instrument [Line Items]
Aggregate principal		$ 230,000
Debt instrument stated rate (percent)		0.75%
Aggregate principal from exercise in full of over-allotment options		$ 30,000
Proceeds from debt offering, net of debt issuance costs		$ 221,400
Conversion ratio		0.0259182
Common stock, par value (in dollars per share) | $ / shares		$ 0.001
Convertible debt conversion price (in dollars per share) | $ / shares		$ 38.58
Percentage of principal amount paid if repurchase due to fundamental change (percent)		100.00%
Threshold trading days in consideration of note conversion | Day		20
Threshold consecutive trading days in analysis of conversion price | Day		30
Threshold percentage of stock price if converted		130.00%
Threshold for five day period, product of sale price of common stock and conversion rate of notes		98.00%
Carry amount of equity component of convertible notes		$ 52,900
Total deferred issuance costs		8,600
Debt issuance costs attributable to liability		6,600
Adjustments to additional paid in capital related to issuance costs attributable to equity component		$ 2,000
Remaining amortization period for debt discount and debt issuance costs		2 years 2 months 12 days
Effective interest rate (percent)		0.0343%
Convertible Debt | 2026 Notes
Debt Instrument [Line Items]
Aggregate principal	$ 517,500			$ 517,500
Debt instrument stated rate (percent)	0.00%			0.00%
Aggregate principal from exercise in full of over-allotment options	$ 67,500			$ 67,500
Proceeds from debt offering, net of debt issuance costs	$ 505,300
Conversion ratio	0.0132933
Common stock, par value (in dollars per share) | $ / shares	$ 0.001			$ 0.001
Convertible debt conversion price (in dollars per share) | $ / shares	$ 75.23			$ 75.23
Percentage of principal amount paid if repurchase due to fundamental change (percent)	100.00%
Threshold trading days in consideration of note conversion | Day	20
Threshold consecutive trading days in analysis of conversion price | Day	30
Threshold percentage of stock price if converted	130.00%
Threshold for five day period, product of sale price of common stock and conversion rate of notes	98.00%
Carry amount of equity component of convertible notes	$ 162,500			$ 162,500
Total deferred issuance costs	12,200			12,200
Debt issuance costs attributable to liability	8,500			$ 8,500
Adjustments to additional paid in capital related to issuance costs attributable to equity component	$ 3,700
Remaining amortization period for debt discount and debt issuance costs			4 years 10 months 24 days
Effective interest rate (percent)			0.0549%