Debt and Liquidity (Summary of Long-Term Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Unamortized debt discount and issuance costs	$ (20,688)	$ (24,494)
Total debt	929,452	925,645
Less: Long-term debt, current portion	(139)	(134)
Long-term debt	929,313	925,511
Secured Notes \| 2020 Senior Secured Notes
Debt Instrument [Line Items]
Long-term debt, gross	500,000	500,000
Secured Notes \| 2023 Senior Secured Notes
Debt Instrument [Line Items]
Long-term debt, gross	450,000	450,000
Other debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 140	$ 139

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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