v3.21.2

Convertible Senior Notes - 0.125% Convertible Notes due 2025 Narrative (Details)	1 Months Ended		3 Months Ended		9 Months Ended	12 Months Ended
	Nov. 30, 2020 USD ($)	Feb. 28, 2018 USD ($)	Mar. 31, 2021 day	Jun. 30, 2018 day	Sep. 30, 2021 USD ($) day $ / shares	Dec. 31, 2020 day
Convertible Notes Due 2025
Debt Instrument [Line Items]
Remaining amortization period for debt discount and debt issuance costs					4 years 1 month 6 days
Convertible Notes Due 2025 | Convertible Debt
Debt Instrument [Line Items]
Interest rate	0.125%
Principal amount	$ 350,000,000
Principal amount received	210,700,000
Principal amount, additional	$ 139,300,000
Initial conversion rate of common stock	0.0071355
Conversion price (usd per share) | $ / shares					$ 140.14
Threshold percentage of stock price trigger					130.00%
Limitation on sale of common stock, sale price threshold, number of trading days | day					20
Limitation on sale of common stock, sale price threshold, trading period | day					30
Number of consecutive business days					5 days
Percentage of closing sale price in excess of convertible notes					98.00%
Redemption price percentage	100.00%
Effective interest rate of liability component					5.00%
Issuance costs attributable to the liability component	$ 5,400,000
Net issuance costs related to the equity component	1,500,000
Shares subject to warrants related to the issuance of the 2023 Notes
Debt Instrument [Line Items]
Remaining amortization period for debt discount and debt issuance costs					1 year 4 months 24 days
Shares subject to warrants related to the issuance of the 2023 Notes | Convertible Debt
Debt Instrument [Line Items]
Interest rate		0.75%
Principal amount		$ 230,000,000			$ 10,900,000
Principal amount exchanged	$ 181,900,000
Initial conversion rate of common stock		0.0174292
Threshold percentage of stock price trigger			130.00%	130.00%	130.00%	130.00%
Limitation on sale of common stock, sale price threshold, number of trading days | day			20	20		20
Limitation on sale of common stock, sale price threshold, trading period | day			30	30	30	30
Number of consecutive business days		5 days
Percentage of closing sale price in excess of convertible notes		98.00%
Redemption price percentage		100.00%
Effective interest rate of liability component		5.875%
Issuance costs attributable to the liability component		$ 5,300,000
Net issuance costs related to the equity component		$ 1,500,000

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