v3.21.2

Convertible Senior Notes - Schedule of Interest Expense Related to 2025 Notes (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Amortization of debt issuance costs		$ 1,550	$ 1,427
Amortization of debt discount		19,398	$ 15,381
Convertible Notes Due 2025 | Convertible Debt
Debt Instrument [Line Items]
Contractual interest expense	$ 109	327
Amortization of debt issuance costs	241	717
Amortization of debt discount	3,416	10,122
Interest Expense	$ 3,766	$ 11,166

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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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