Segment Reporting (Summary Of The Operating Information) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 30, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Revenues	$ 1,389,877	$ 1,292,861
Cost of revenues	253,204	231,278
Operating expenses	938,729	866,368
Total costs and expenses	1,191,933	1,097,646
Operating earnings (loss)	197,944	195,215
Domestic Segment
Segment Reporting Information [Line Items]
Revenues	1,230,830	1,135,096
Cost of revenues	228,559	206,674
Operating expenses	572,018	519,871
Total costs and expenses	800,577	726,545
Operating earnings (loss)	430,253	408,551
International Segment [Member]
Segment Reporting Information [Line Items]
Revenues	159,047	157,765
Cost of revenues	24,645	24,604
Operating expenses	68,169	69,144
Total costs and expenses	92,814	93,748
Operating earnings (loss)	66,233	64,017
Other
Segment Reporting Information [Line Items]
Operating expenses	298,542	277,353
Total costs and expenses	298,542	277,353
Operating earnings (loss)	$ (298,542)	$ (277,353)