0.5% Convertible Senior Notes and Capped Call - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Debt Instrument [Line Items]
Total interest expense	$ 6,091	$ 5,790
Convertible Debt \| Convertible Senior Notes Due 2023
Debt Instrument [Line Items]
Amortization of debt discount	436	389
Amortization of issuance costs	625	625
Contractual interest expense	$ 5,030	$ 4,776

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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