Convertible Senior Notes and Capped Call Transactions - Schedule of Interest Expense Incurred (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Amortization of debt issuance costs			$ 1,858	$ 908
Accretion of debt discount on convertible senior notes			24,770	7,227
Convertible Senior Notes \| Convertible Debt
Debt Instrument [Line Items]
Contractual interest expense	$ 431	$ 431	1,294	1,294
Amortization of debt issuance costs	630	308	1,858	908
Accretion of debt discount on convertible senior notes	8,396	2,450	24,770	7,227
Total interest expense	$ 9,457	$ 3,189	$ 27,922	$ 9,429

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Amount of amortization expense attributable to debt issuance costs.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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