Debt And Liquidity (Summary Of Long-Term Debt) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Debt Instrument [Line Items]
Unamortized debt discount and issuance costs	$ (12,678)		$ (14,449)
Total debt	961,449		1,029,688
Less: Short-term debt	(125)		(127)
Long-term debt	961,324		1,029,561
Repayments of Long-term Debt	70,000	$ 150,000
Fair Value, Inputs, Level 3
Debt Instrument [Line Items]
Fair Value of Debt	933,100		1,051,600
2018 Term Loan Facility
Debt Instrument [Line Items]
Repayments of Long-term Debt	70,000	$ 150,000
2018 Term Loan Facility
Debt Instrument [Line Items]
Long-term Debt, Gross	473,708		543,708
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	$ 419		$ 429

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, 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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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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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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