Convertible Senior Notes - Expenses and Interest (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Debt Instrument [Line Items]
Amortization of Debt Issuance Costs	$ 1,092	$ 2,716
3.75% Convertible Senior Notes
Debt Instrument [Line Items]
Interest Expense	1,897
Amortization of Debt Issuance Costs	1,258
Total	$ 3,155
Effective Interest Rate	4.50%

Amount of amortization expense attributable to debt issuance costs.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Interest and debt related expenses associated with nonoperating financing activities of the entity.

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

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