Indebtedness - Schedule of Interest Expense Recognized (Details) - 5.00% Convertible Senior Notes Due 2027 - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Contractual interest expense	$ 1,139	$ 0
Amortization of debt discount	3	0
Amortization of interest expense	642	0
Total interest expense related to the 2027 Notes	$ 1,784	$ 0

Contractual 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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- Definition

Amount of amortization expense attributable to debt issuance costs.

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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.

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- Definition

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

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