Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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Face (par) amount of debt instrument at time of issuance.

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No definition available.

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Debt - Reconciliation of Convertible Debt (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2019
Debt Instrument [Line Items]
Carrying value	$ 216,088,000	$ 210,373,000
Convertible notes
Debt Instrument [Line Items]
Gross proceeds				$ 316,250,000
Convertible Senior Notes Due 2024 \| Convertible notes
Debt Instrument [Line Items]
Gross proceeds	316,250,000	316,250,000
Unamortized debt discount	(96,083,000)	(101,565,000)
Unamortized issuance costs	(4,079,000)	(4,312,000)	$ (5,500,000)
Carrying value	$ 216,088,000	$ 210,373,000