Segment Information (Summary Of Inter-Segment Eliminations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Revenues, Net	$ 435,247	$ 395,328	$ 379,322	$ 381,961	$ 366,712	$ 332,056	$ 327,570	$ 326,239	$ 1,591,858	$ 1,352,577	$ 1,187,741
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues, Net									(15,587)	(16,150)	(20,190)
Intersegment Eliminations [Member] | National Networks [Member]
Segment Reporting Information [Line Items]
Revenues, Net									(184)	(569)	(454)
Intersegment Eliminations [Member] | International and Other [Member]
Segment Reporting Information [Line Items]
Revenues, Net									$ (15,403)	$ (15,581)	$ (19,736)