Segment Reporting (Schedule Of Net Revenues Earned On Major Geographical Areas) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Segment Reporting Information [Line Items]
Total net revenues	[1]	$ 1,284,286	$ 1,217,932	$ 2,539,755	$ 2,380,970
United States [Member]
Segment Reporting Information [Line Items]
Total net revenues		1,224,193	1,147,168	2,405,653	2,248,172
United Kingdom [Member]
Segment Reporting Information [Line Items]
Total net revenues		41,336	42,698	89,580	80,223
Canada [Member]
Segment Reporting Information [Line Items]
Total net revenues		9,091	10,610	25,570	22,230
Other [Member]
Segment Reporting Information [Line Items]
Total net revenues		$ 9,666	$ 17,456	$ 18,952	$ 30,345

[1] No individual client accounted for more than 10 percent of total net revenues for the three and six months ended June 30, 2025 and 2024.