Share-Based Compensation (Compensation Expense Recognized In The Condensed Consolidated Statements Of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amounts charged against earnings, before income tax benefit	$ 55,666	$ 38,137	$ 157,592	$ 111,724
Amount of related income tax benefit recognized in earnings	11,155	7,818	31,602	22,452
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	55,274	37,920	157,165	110,500
Associate stock purchase plan expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amounts charged against earnings, before income tax benefit	1,300	1,367	4,461	4,195
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	$ (908)	$ (1,150)	$ (4,034)	$ (2,971)