Convertible Senior Notes - Summary of the Components of Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Amortization of discount on convertible senior notes		$ 249	$ 0
Amortization of debt issuance costs		754	$ 1,718
Convertible Senior Notes \| Convertible Debt
Debt Instrument [Line Items]
Contractual coupon interest	$ 20	20
Amortization of discount on convertible senior notes	249	249
Amortization of debt issuance costs	$ 31	$ 31

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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