Business Segment Information - Schedule Of Additional Information Pertaining To Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Segment Reporting Information [Line Items]
Amortization	$ 18,354	$ 10,710
Depreciation	7,256	7,927
Operating Segments
Segment Reporting Information [Line Items]
Amortization	18,269	10,646
Depreciation	6,803	4,743
Operating Segments \| Investment Managers
Segment Reporting Information [Line Items]
Amortization	1,711	202
Depreciation	1,813	62
Operating Segments \| Private Banks
Segment Reporting Information [Line Items]
Amortization	5,645	5,275
Depreciation	2,638	2,259
Operating Segments \| Investment Advisors
Segment Reporting Information [Line Items]
Amortization	8,541	2,419
Depreciation	1,771	2,025
Operating Segments \| Institutional Investors
Segment Reporting Information [Line Items]
Amortization	1,956	1,875
Depreciation	464	319
Operating Segments \| Investments In New Businesses
Segment Reporting Information [Line Items]
Amortization	416	875
Depreciation	117	78
Corporate overhead
Segment Reporting Information [Line Items]
Amortization	85	64
Depreciation	$ 453	$ 3,184

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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- Definition

The expense recognized in the current period that allocates the cost of nonproduction tangible assets over their useful lives.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-1

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- Definition

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.

+ References

No definition available.

+ Details

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