Debt And Liquidity (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total	$ 1,812,823	$ 2,156,634	$ 2,156,600
Less: Short-term Debt	(141)	(106,323)
Long-term debt	1,812,682	2,050,311
Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Total	1,812,204	2,155,883
Other Debt [Member]
Debt Instrument [Line Items]
Total	$ 619	$ 751