Convertible Senior Notes and Capped Call Transactions - Schedule of Interest Expense Incurred (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Debt Instrument [Line Items]
Amortization of debt issuance costs			$ 1,228	$ 600
Accretion of debt discount on convertible senior notes			16,374	4,777
Convertible Senior Notes \| Convertible Debt
Debt Instrument [Line Items]
Contractual interest expense	$ 432	$ 431	863	863
Amortization of debt issuance costs	619	303	1,228	600
Accretion of debt discount on convertible senior notes	8,256	2,409	16,374	4,776
Total interest expense	$ 9,307	$ 3,143	$ 18,465	$ 6,239

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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