Long-Term Debt Schedule of Long-Term Debt Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Feb. 16, 2018
Debt Instrument [Line Items]
Total	$ 121,686	$ 115,840
Other debt	55	594
Less: current maturities	0	(106)
Long-term debt, less current portion	$ 121,686	$ 115,734
4.50% Exchangeable Senior Notes Due 2023
Debt Instrument [Line Items]
Interest rate	4.50%	4.50%	4.50%
Senior Notes
Debt Instrument [Line Items]
Less: debt discount and issuance costs, net	$ (22,064)	$ (28,059)
Total	121,686	115,691
Equity component of exchangeable notes, net of issuance costs	(26,699)	(26,699)
Senior Notes \| 4.50% Exchangeable Senior Notes Due 2023
Debt Instrument [Line Items]
Long-term debt	143,750	143,750
Loans Payable
Debt Instrument [Line Items]
Other debt	$ 0	$ 149

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

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