Debt - Interest Expense Recognized (Details) - Convertible senior notes - Convertible senior notes - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Contractual interest expense		$ 4,313	$ 2,707
Amortization of debt issuance costs		1,727	652
Amortization of debt discount			9,446
Total interest expense		$ 6,040	$ 12,805

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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