Segment Information (Summary Of Continuing Operations By Reportable Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting Information [Line Items]
Advertising	$ 207,490	$ 180,311	$ 486,732	$ 396,228
Distribution	393,648	341,782	783,088	650,419
Consolidated revenues, net	601,138	522,093	1,269,820	1,046,647
Adjusted operating cash flow	191,329	156,919	450,547	324,025
Depreciation and amortization	(21,040)	(17,531)	(41,567)	(31,925)
Share-based compensation expense	(8,801)	(8,760)	(16,089)	(13,839)
Restructuring Charges	(2,654)	(1,153)	(3,310)	(1,153)
Operating income	158,834	129,475	389,581	277,108
Capital Expenditures			33,124	18,755
National Networks [Member]
Segment Reporting Information [Line Items]
Restructuring Charges	(651)		(717)
International And Other [Member]
Segment Reporting Information [Line Items]
Restructuring Charges	(2,003)		(2,593)
Operating Segments [Member] | National Networks [Member]
Segment Reporting Information [Line Items]
Advertising	185,712	163,836	446,151	371,739
Distribution	302,896	234,168	605,304	474,945
Consolidated revenues, net	488,608	398,004	1,051,455	846,684
Adjusted operating cash flow	182,553	136,918	435,811	314,664
Depreciation and amortization	(7,212)	(5,046)	(14,574)	(9,953)
Share-based compensation expense	(7,043)	(6,624)	(12,453)	(10,789)
Restructuring Charges	(651)	0	(717)	0
Operating income	167,647	125,248	408,067	293,922
Capital Expenditures			11,484	7,204
Operating Segments [Member] | International And Other [Member]
Segment Reporting Information [Line Items]
Advertising	21,778	16,475	40,581	24,489
Distribution	91,105	108,125	178,658	176,689
Consolidated revenues, net	112,883	124,600	219,239	201,178
Adjusted operating cash flow	8,610	19,537	14,289	8,488
Depreciation and amortization	(13,828)	(12,485)	(26,993)	(21,972)
Share-based compensation expense	(1,758)	(2,136)	(3,636)	(3,050)
Restructuring Charges	(2,003)	(1,153)	(2,593)	(1,153)
Operating income	(8,979)	3,763	(18,933)	(17,687)
Capital Expenditures			21,640	11,551
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Advertising	0	0	0	0
Distribution	(353)	(511)	(874)	(1,215)
Consolidated revenues, net	(353)	(511)	(874)	(1,215)
Adjusted operating cash flow	166	464	447	873
Depreciation and amortization	0	0	0	0
Share-based compensation expense	0	0	0	0
Restructuring Charges	0	0	0	0
Operating income	166	464	447	873
Capital Expenditures			0	0
Intersegment Eliminations [Member] | National Networks [Member]
Segment Reporting Information [Line Items]
Consolidated revenues, net	(336)	(316)	(788)	(990)
Intersegment Eliminations [Member] | International And Other [Member]
Segment Reporting Information [Line Items]
Consolidated revenues, net	$ (17)	$ (195)	$ (86)	$ (225)