Business Segment Information - Schedule Of Additional Information Pertaining To Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Segment Reporting [Line Items]
Amortization	$ 19,684	$ 11,912	$ 57,175	$ 33,071
Depreciation	7,119	7,485	21,446	23,077
Operating Segments
Segment Reporting [Line Items]
Amortization	19,574	11,573	56,895	32,574
Depreciation	6,627	6,954	20,049	18,828
Operating Segments \| Investment Managers
Segment Reporting [Line Items]
Amortization	1,700	1,301	5,109	1,704
Depreciation	1,764	1,788	5,372	3,582
Operating Segments \| Private Banks
Segment Reporting [Line Items]
Amortization	5,634	5,427	16,943	16,046
Depreciation	2,645	2,681	7,870	7,634
Operating Segments \| Investment Advisors
Segment Reporting [Line Items]
Amortization	9,871	2,473	27,737	7,342
Depreciation	1,689	1,889	5,128	5,914
Operating Segments \| Institutional Investors
Segment Reporting [Line Items]
Amortization	1,953	1,956	5,859	5,775
Depreciation	420	474	1,339	1,287
Operating Segments \| Investments In New Businesses
Segment Reporting [Line Items]
Amortization	416	416	1,247	1,707
Depreciation	109	122	340	411
Corporate overhead
Segment Reporting [Line Items]
Amortization	110	339	280	497
Depreciation	$ 492	$ 531	$ 1,397	$ 4,249

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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