Debt And Liquidity (Summary Of Long-Term Debt) (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Unamortized debt discount and issuance costs	$ (11,353)	$ (12,049)
Total debt	922,628	921,927
Less: Long-term debt, current portion	(128)	(124)
Long-term debt	922,500	921,803
2018 Term Loan Facility
Debt Instrument [Line Items]
Long-term Debt, Gross	433,708	433,708
2020 Senior Secured Notes
Debt Instrument [Line Items]
Long-term Debt, Gross	500,000	500,000
Other debt
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 273	$ 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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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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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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