Debt and Liquidity (Summary of Long-Term Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 26, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Unamortized debt discount and issuance costs	$ (25,764)		$ (12,049)
Total debt	924,502		921,927
Less: Long-term debt, current portion	(127)		(124)
Long-term debt	924,375		921,803
2018 Term Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross	0	$ 433,700	433,708
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		0
Other debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 266		$ 268

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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