Convertible Senior Notes and Capped Call Transactions - Summary of Interest Expense Recognized Related to Notes (Details) - Convertible Senior Notes due 2024 $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Interest Expense Debt [Line Items]
Contractual interest expense	$ 125
Amortization of debt discount	3,989
Amortization of debt issuance costs	337
Total	$ 4,451

Interest expense debt.

No definition available.

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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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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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