Basis Of Presentation And Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Investment Holdings [Line Items]
Decrease in carrying value of debt					$ 50,000
Impairment of Long-Lived Assets Held-for-use	$ 37,000
Operating revenues	518,069	$ 488,594	$ 1,564,697	$ 1,462,855
Operating profit	222,420	38,808	295,776	119,527
Variable Interest Entity, Primary Beneficiary | Dreamcatcher Stations
Investment Holdings [Line Items]
Operating revenues	17,000	16,000	52,000	48,000
Operating profit	$ 3,000	$ 2,000	$ 10,000	$ 9,000