Business Segment Information - Schedule Of Additional Information Pertaining To Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Segment Reporting [Line Items]
Amortization	$ 19,137	$ 10,449	$ 37,491	$ 21,159
Depreciation	7,071	7,665	14,327	15,592
Operating Segments
Segment Reporting [Line Items]
Amortization	19,052	10,355	37,321	21,001
Depreciation	6,619	7,131	13,422	11,874
Operating Segments \| Investment Managers
Segment Reporting [Line Items]
Amortization	1,698	201	3,409	403
Depreciation	1,795	1,732	3,608	1,794
Operating Segments \| Private Banks
Segment Reporting [Line Items]
Amortization	5,664	5,344	11,309	10,619
Depreciation	2,587	2,694	5,225	4,953
Operating Segments \| Investment Advisors
Segment Reporting [Line Items]
Amortization	9,325	2,450	17,866	4,869
Depreciation	1,668	2,000	3,439	4,025
Operating Segments \| Institutional Investors
Segment Reporting [Line Items]
Amortization	1,950	1,944	3,906	3,819
Depreciation	455	494	919	813
Operating Segments \| Investments In New Businesses
Segment Reporting [Line Items]
Amortization	415	416	831	1,291
Depreciation	114	211	231	289
Corporate overhead
Segment Reporting [Line Items]
Amortization	85	94	170	158
Depreciation	$ 452	$ 534	$ 905	$ 3,718

The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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