Segment Information (Summary Of Continuing Operations By Reportable Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Advertising	$ 210,724	$ 230,839	$ 762,320	$ 717,571
Distribution	423,922	401,326	1,263,737	1,184,414
Consolidated revenues, net	634,646	632,165	2,026,057	1,901,985
Adjusted operating income	168,113	190,582	665,830	641,129
Depreciation and amortization	(22,282)	(20,862)	(63,467)	(62,429)
Share-based compensation expense	(9,382)	(7,821)	(28,869)	(23,910)
Restructuring expense	(19,312)	(2,631)	(19,666)	(5,941)
Operating income	117,137	159,268	553,828	548,849
Capital expenditures			44,505	48,810
National Networks [Member]
Segment Reporting Information [Line Items]
Restructuring expense	(8,103)	(100)	(8,170)	(817)
International And Other [Member]
Segment Reporting Information [Line Items]
Restructuring expense	(11,209)	(2,531)	(11,496)	(5,124)
Operating Segments [Member] | National Networks [Member]
Segment Reporting Information [Line Items]
Advertising	189,300	210,194	692,483	656,345
Distribution	336,413	311,446	1,004,499	916,751
Consolidated revenues, net	525,713	521,640	1,696,982	1,573,096
Adjusted operating income	162,503	186,574	649,782	622,385
Depreciation and amortization	(8,040)	(7,337)	(24,062)	(21,911)
Share-based compensation expense	(7,212)	(6,039)	(22,581)	(18,492)
Restructuring expense	(8,103)	(100)	(8,170)	(817)
Operating income	139,148	173,098	594,969	581,165
Capital expenditures			10,165	17,095
Operating Segments [Member] | International And Other [Member]
Segment Reporting Information [Line Items]
Advertising	21,424	20,645	69,837	61,226
Distribution	92,596	93,458	271,511	272,115
Consolidated revenues, net	114,020	114,103	341,348	333,341
Adjusted operating income	10,953	6,749	24,118	21,038
Depreciation and amortization	(14,242)	(13,525)	(39,405)	(40,518)
Share-based compensation expense	(2,170)	(1,782)	(6,288)	(5,418)
Restructuring expense	(11,209)	(2,531)	(11,496)	(5,124)
Operating income	(16,668)	(11,089)	(33,071)	(30,022)
Capital expenditures			34,340	31,715
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Advertising	0	0	0	0
Distribution	(5,087)	(3,578)	(12,273)	(4,452)
Consolidated revenues, net	(5,087)	(3,578)	(12,273)	(4,452)
Adjusted operating income	(5,343)	(2,741)	(8,070)	(2,294)
Depreciation and amortization	0	0	0	0
Share-based compensation expense	0	0	0	0
Restructuring expense	0	0	0	0
Operating income	(5,343)	(2,741)	(8,070)	(2,294)
Capital expenditures			0	0
Intersegment Eliminations [Member] | National Networks [Member]
Segment Reporting Information [Line Items]
Consolidated revenues, net	(5,079)	(3,563)	(12,015)	(4,351)
Intersegment Eliminations [Member] | International And Other [Member]
Segment Reporting Information [Line Items]
Consolidated revenues, net	$ (8)	$ (15)	$ (258)	$ (101)