Business Segment Information - Schedule Of Additional Information Pertaining To Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting Information [Line Items]
Capital Expenditures	$ 16,980	$ 12,138	$ 43,897	$ 45,617
Depreciation	7,485	8,341	23,077	25,097
Amortization	11,912	10,413	33,071	31,284
Operating Segments
Segment Reporting Information [Line Items]
Capital Expenditures	16,530	11,916	42,911	44,588
Depreciation	6,954	7,333	18,828	22,199
Amortization	11,573	10,343	32,574	31,027
Operating Segments \| Investment Managers
Segment Reporting Information [Line Items]
Capital Expenditures	6,054	7,196	16,690	21,260
Depreciation	1,788	1,659	3,582	4,874
Amortization	1,301	80	1,704	161
Operating Segments \| Private Banks
Segment Reporting Information [Line Items]
Capital Expenditures	6,479	2,764	16,192	13,782
Depreciation	2,681	2,620	7,634	8,356
Amortization	5,427	5,147	16,046	15,347
Operating Segments \| Investment Advisors
Segment Reporting Information [Line Items]
Capital Expenditures	2,978	1,092	7,512	6,244
Depreciation	1,889	2,254	5,914	6,625
Amortization	2,473	2,169	7,342	6,439
Operating Segments \| Institutional Investors
Segment Reporting Information [Line Items]
Capital Expenditures	761	740	1,859	2,589
Depreciation	474	614	1,287	1,816
Amortization	1,956	1,851	5,775	5,619
Operating Segments \| Investments In New Businesses
Segment Reporting Information [Line Items]
Capital Expenditures	258	124	658	713
Depreciation	122	186	411	528
Amortization	416	1,096	1,707	3,461
Corporate overhead
Segment Reporting Information [Line Items]
Capital Expenditures	450	222	986	1,029
Depreciation	531	1,008	4,249	2,898
Amortization	$ 339	$ 70	$ 497	$ 257

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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Future cash outflow to pay for purchases of fixed assets that have occurred.

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-Name Accounting Standards Codification
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The expense recognized in the current period that allocates the cost of nonproduction tangible assets over their useful lives.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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