Long-term Debt - Liability and Equity Component of Note (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Liability component:
Net carrying amount	$ 187,737	$ 124,664
Convertible debt \| 2023 Notes
Liability component:
Principal	12,510	143,750
Less: Unamortized debt discount	(1,137)	(16,033)
Unamortized debt issuance costs	(212)	(3,053)
Net carrying amount	11,161	124,664
Convertible debt \| 2025 Notes
Liability component:
Principal	230,000	0
Less: Unamortized debt discount	(47,827)	0
Unamortized debt issuance costs	(5,597)	0
Net carrying amount	$ 176,576	$ 0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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