Long-Term Debt Schedule of Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Net carrying amount of liability component	$ 117,282	$ 115,840
Other debt	66	594
Less: current maturities	(104)	(106)
Long-term debt, less current portion	117,178	115,734
Senior Notes
Debt Instrument [Line Items]
Less: debt discount and issuance costs, net	(26,614)	(28,059)
Net carrying amount of liability component	117,136	115,691
Equity component of exchangeable notes, net of issuance costs	(26,699)	(26,699)
Loans Payable
Debt Instrument [Line Items]
Other debt	$ 146	$ 149
4.50% Exchangeable Senior Notes Due 2023
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	4.50%	4.50%
4.50% Exchangeable Senior Notes Due 2023 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 143,750	$ 143,750

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. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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