Debt And Liquidity (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total	$ 1,029,688	$ 1,420,131
Long-term debt	1,029,561	1,420,000
Senior Secured Credit Facility
Debt Instrument [Line Items]
Long-term Debt, Gross	543,708	943,708
Secured Debt
Debt Instrument [Line Items]
Long-term Debt, Gross	500,000	500,000
Other Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	429	615
Unamortized Financing Costs member
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(14,449)	(24,192)
2018 Credit Agreement [Member]
Debt Instrument [Line Items]
Less: Short-term Debt	$ (127)	$ (131)

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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