Business Segment Information (Schedule Of Additional Information Pertaining To Business Segments) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Segment Reporting Information [Line Items]
Capital expenditure	$ 14,130	$ 15,229	$ 33,479	$ 34,850
Depreciation	8,367	8,781	16,756	17,312
Amortization	10,485	9,630	20,871	19,054
Operating Segments
Segment Reporting Information [Line Items]
Capital expenditure	13,865	14,867	32,672	33,873
Depreciation	7,426	8,575	14,866	16,902
Amortization	10,377	9,565	20,684	18,925
Operating Segments \| Private Banks
Segment Reporting Information [Line Items]
Capital expenditure	4,586	8,001	11,018	17,072
Depreciation	2,832	5,450	5,736	10,804
Amortization	5,089	4,718	10,200	9,364
Operating Segments \| Investment Advisors
Segment Reporting Information [Line Items]
Capital expenditure	1,987	3,615	5,152	7,954
Depreciation	2,190	549	4,371	1,017
Amortization	2,148	1,945	4,270	3,763
Operating Segments \| Institutional Investors
Segment Reporting Information [Line Items]
Capital expenditure	730	457	1,849	1,105
Depreciation	598	303	1,202	585
Amortization	1,876	1,829	3,768	3,653
Operating Segments \| Investment Managers
Segment Reporting Information [Line Items]
Capital expenditure	6,389	2,592	14,064	7,158
Depreciation	1,636	2,049	3,215	4,041
Amortization	81	181	81	358
Operating Segments \| Investments In New Businesses
Segment Reporting Information [Line Items]
Capital expenditure	173	202	589	584
Depreciation	170	224	342	455
Amortization	1,183	892	2,365	1,787
Corporate overhead
Segment Reporting Information [Line Items]
Capital expenditure	265	362	807	977
Depreciation	941	206	1,890	410
Amortization	$ 108	$ 65	$ 187	$ 129

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.

+ References

No definition available.

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