Business Segment Information - Schedule of Financial Information About Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Total revenue	$ 551,344	$ 511,579
Operations & services	203,197	192,228
Sales, marketing & client service	42,520	41,921
Technology services & infrastructure	52,870	48,462
Strategic initiatives & new business development	48,731	51,398
Other segment expenses	11,463	13,965
Segment profit (loss)	192,563	163,605
Investment Managers
Segment Reporting Information [Line Items]
Total revenue	192,048	172,653
Operations & services	86,239	78,374
Sales, marketing & client service	9,832	9,827
Technology services & infrastructure	12,752	10,454
Strategic initiatives & new business development	6,387	7,989
Other segment expenses	2,001	2,906
Segment profit (loss)	74,837	63,103
Private Banks
Segment Reporting Information [Line Items]
Total revenue	137,714	130,137
Operations & services	50,286	48,262
Sales, marketing & client service	8,910	10,774
Technology services & infrastructure	28,335	26,906
Strategic initiatives & new business development	22,379	21,258
Other segment expenses	4,839	5,774
Segment profit (loss)	22,965	17,163
Investment Advisors
Segment Reporting Information [Line Items]
Total revenue	136,576	122,718
Operations & services	41,038	39,051
Sales, marketing & client service	9,195	5,220
Technology services & infrastructure	8,866	8,329
Strategic initiatives & new business development	11,708	12,548
Other segment expenses	1,648	1,810
Segment profit (loss)	64,121	55,760
Institutional Investors
Segment Reporting Information [Line Items]
Total revenue	68,506	71,778
Operations & services	20,673	21,623
Sales, marketing & client service	9,656	11,493
Technology services & infrastructure	1,549	1,477
Strategic initiatives & new business development	2,559	3,585
Other segment expenses	1,433	1,931
Segment profit (loss)	32,636	31,669
Investments In New Businesses
Segment Reporting Information [Line Items]
Total revenue	16,500	14,293
Operations & services	4,961	4,918
Sales, marketing & client service	4,927	4,607
Technology services & infrastructure	1,368	1,296
Strategic initiatives & new business development	5,698	6,018
Other segment expenses	1,542	1,544
Segment profit (loss)	$ (1,996)	$ (4,090)

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Business development involves the development of products and services, their delivery, design and their implementation. Business development includes a number of techniques designed to grow an economic enterprise. Such techniques include, but are not limited to, assessments of marketing opportunities and target markets, intelligence gathering on customers and competitors, generating leads for possible sales, follow-up sales activity, formal proposal writing and business model design. Business development involves evaluating a business and then realizing its full potential, using such tools as marketing, sales, information management and customer service.

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