v3.21.2

Convertible Senior Notes - 0.75% Convertible Notes due 2026 Narrative (Details) - Convertible Senior Notes Due June 2026	1 Months Ended	3 Months Ended	9 Months Ended
	Jun. 30, 2019 USD ($) day	Sep. 30, 2019 day	Sep. 30, 2021 $ / shares
Debt Instrument [Line Items]
Remaining amortization period for debt discount and debt issuance costs			4 years 8 months 12 days
Convertible Debt
Debt Instrument [Line Items]
Interest rate	0.75%
Principal amount	$ 316,300,000
Initial conversion rate of common stock			0.0112851
Conversion price (usd per share) | $ / shares			$ 88.61
Threshold percentage of stock price trigger	130.00%	130.00%
Limitation on sale of common stock, sale price threshold, number of trading days | day	20	20
Limitation on sale of common stock, sale price threshold, trading period | day	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	5.38%
Issuance costs attributable to the liability component	$ 6,400,000
Net issuance costs related to the equity component	$ 2,900,000

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