Lines of Credit and Long-Term Debt - Long-term debt (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Capital Lease Obligations
Long term debt, gross	$ 325,000	$ 325,000
Unamortized discount, including debt issuance costs, on convertible senior subordinated notes	(92,342)	(98,709)
Long term debt, net	232,658	226,291
Finance leases	8	128
Total long-term debt and finance leases, net	232,666	226,419
Less current portion, net	(8)	(125)
Long-term debt and finance leases, net	$ 232,658	$ 226,294

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 of unamortized debt discount (premium) and debt issuance costs.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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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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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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Amount of long-term debt and lease obligation, including portion classified as current.

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