Long-Term Debt and Interest Expense (Schedule Of Interest Expense) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Long-Term Debt and Interest Expense [Abstract]
Cash payments for interest	$ 18,698	$ 18,875
Commitment and other fees paid	673	407
Amortization of debt issuance costs and discount or premium on notes	2,922	681
Change in accrued interest	(1,607)	(2,989)
Other	28	(111)
Total interest expense	$ 20,714	$ 16,863