Note 8 - Convertible Debt - Carry Amount of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Principal	$ 517,500	$ 517,500
Unamortized debt discount	(38,105)	(64,222)
Unamortized debt issuance costs	(3,217)	(5,453)
Net carrying amount of long-term debt	476,178	447,825
Less current portion of long-term debt	217,467	0
Long-term debt, non-current portion	$ 258,711	$ 447,825

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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