Convertible Senior Notes - Summary of Interest Expense (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Debt Disclosure [Abstract]
Contractual interest expense	$ 970
Amortization of debt discount	1,953
Amortization of issuance costs	244
Total interest expense	$ 3,167

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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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

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