Convertible Senior Notes and Capped Call Transactions - Schedule of Carrying Amount of Liability Component of Convertible Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Carrying Amount of Liability Component:
Net carrying amount	$ 565,059	$ 538,432
Convertible Debt \| Convertible Senior Notes
Carrying Amount of Liability Component:
Principal	747,500	747,500
Unamortized discount	(171,500)	(196,269)
Unamortized issuance costs	$ (10,941)	$ (12,799)

Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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- Definition

Amount, after accumulated amortization, of debt discount.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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No definition available.

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- Details

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