Debt Facilities - Schedule of Interest Expense (Details) - 2019 Convertible Senior Notes due 2026 - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Debt Instrument [Line Items]
Amortization of debt discount		$ 854
Amortization of debt issuance costs	$ 94	26
Cash interest expense	431	431
Total interest expense	$ 525	$ 1,311

Cash interest expense.

No definition available.

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- Definition

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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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