Share-Based Compensation (Compensation Expense Recognized In The Condensed Consolidated Statements Of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amounts charged against earnings, before income tax benefit	$ 26,882	$ 21,359	$ 79,620	$ 63,368
Amount of related income tax benefit recognized in earnings	5,615	6,226	16,483	18,289
Stock option and non-vested share compensation expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amounts charged against earnings, before income tax benefit	25,209	19,858	74,348	59,217
Associate stock purchase plan expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amounts charged against earnings, before income tax benefit	1,407	1,546	4,685	4,516
Amounts capitalized in software development costs, net of amortization
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amounts charged against earnings, before income tax benefit	$ 266	$ (45)	$ 587	$ (365)