Long-Term Debt Schedule of Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Less: current maturities	$ 0	$ 0
Long-term debt	141,774	128,210
Senior Notes
Debt Instrument [Line Items]
Less: unamortized debt discount and issuance costs, net	(1,976)	(15,540)
Net carrying amount of liability component	141,774	128,210
Equity component of exchangeable notes, net of issuance costs	0	(26,699)
Senior Notes \| 4.50% Exchangeable Senior Notes Due 2023
Debt Instrument [Line Items]
Principal amount of 4.50% exchangeable senior notes due 2023	$ 143,750	$ 143,750
Debt instrument, interest rate, stated percentage	4.50%	4.50%

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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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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Contractual interest rate for funds borrowed, under the debt agreement.

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

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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, 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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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