Revenues from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Disaggregation of Revenue [Line Items]
Total revenue	$ 551,344	$ 511,579
United States
Disaggregation of Revenue [Line Items]
Total revenue	472,682	438,121
United Kingdom
Disaggregation of Revenue [Line Items]
Total revenue	38,336	39,066
Canada
Disaggregation of Revenue [Line Items]
Total revenue	11,398	11,270
Ireland
Disaggregation of Revenue [Line Items]
Total revenue	20,975	16,334
Luxembourg
Disaggregation of Revenue [Line Items]
Total revenue	7,953	6,788
Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Total revenue	97,935	103,510
Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Total revenue	110,156	107,609
Investment operations fees
Disaggregation of Revenue [Line Items]
Total revenue	202,960	175,850
Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Total revenue	79,139	70,818
Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Total revenue	30,857	30,663
Professional services fees
Disaggregation of Revenue [Line Items]
Total revenue	9,608	5,715
Account fees and other
Disaggregation of Revenue [Line Items]
Total revenue	20,689	17,414
Investment Managers
Disaggregation of Revenue [Line Items]
Total revenue	192,048	172,653
Investment Managers \| United States
Disaggregation of Revenue [Line Items]
Total revenue	170,036	155,959
Investment Managers \| United Kingdom
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Investment Managers \| Canada
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Investment Managers \| Ireland
Disaggregation of Revenue [Line Items]
Total revenue	14,059	9,906
Investment Managers \| Luxembourg
Disaggregation of Revenue [Line Items]
Total revenue	7,953	6,788
Investment Managers \| Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Total revenue	109	84
Investment Managers \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Investment Managers \| Investment operations fees
Disaggregation of Revenue [Line Items]
Total revenue	180,357	164,189
Investment Managers \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Total revenue	1,287	1,258
Investment Managers \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Total revenue	0	19
Investment Managers \| Professional services fees
Disaggregation of Revenue [Line Items]
Total revenue	1,709	1,017
Investment Managers \| Account fees and other
Disaggregation of Revenue [Line Items]
Total revenue	8,586	6,086
Private Banks
Disaggregation of Revenue [Line Items]
Total revenue	137,714	130,137
Private Banks \| United States
Disaggregation of Revenue [Line Items]
Total revenue	93,131	85,775
Private Banks \| United Kingdom
Disaggregation of Revenue [Line Items]
Total revenue	29,767	29,848
Private Banks \| Canada
Disaggregation of Revenue [Line Items]
Total revenue	9,983	9,799
Private Banks \| Ireland
Disaggregation of Revenue [Line Items]
Total revenue	4,833	4,715
Private Banks \| Luxembourg
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Private Banks \| Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Total revenue	30,743	32,399
Private Banks \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Total revenue	1,058	931
Private Banks \| Investment operations fees
Disaggregation of Revenue [Line Items]
Total revenue	622	539
Private Banks \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Total revenue	75,856	67,846
Private Banks \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Total revenue	21,815	23,459
Private Banks \| Professional services fees
Disaggregation of Revenue [Line Items]
Total revenue	6,914	4,115
Private Banks \| Account fees and other
Disaggregation of Revenue [Line Items]
Total revenue	706	848
Investment Advisors
Disaggregation of Revenue [Line Items]
Total revenue	136,576	122,718
Investment Advisors \| United States
Disaggregation of Revenue [Line Items]
Total revenue	136,576	122,718
Investment Advisors \| United Kingdom
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Investment Advisors \| Canada
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Investment Advisors \| Ireland
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Investment Advisors \| Luxembourg
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Investment Advisors \| Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Total revenue	55,104	58,597
Investment Advisors \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Total revenue	52,077	48,161
Investment Advisors \| Investment operations fees
Disaggregation of Revenue [Line Items]
Total revenue	20,837	9,644
Investment Advisors \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Total revenue	1,364	1,281
Investment Advisors \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Total revenue	1,382	0
Investment Advisors \| Professional services fees
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Investment Advisors \| Account fees and other
Disaggregation of Revenue [Line Items]
Total revenue	5,812	5,035
Institutional Investors
Disaggregation of Revenue [Line Items]
Total revenue	68,506	71,778
Institutional Investors \| United States
Disaggregation of Revenue [Line Items]
Total revenue	57,009	59,376
Institutional Investors \| United Kingdom
Disaggregation of Revenue [Line Items]
Total revenue	7,999	9,218
Institutional Investors \| Canada
Disaggregation of Revenue [Line Items]
Total revenue	1,415	1,471
Institutional Investors \| Ireland
Disaggregation of Revenue [Line Items]
Total revenue	2,083	1,713
Institutional Investors \| Luxembourg
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Institutional Investors \| Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Total revenue	11,576	12,074
Institutional Investors \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Total revenue	52,237	54,209
Institutional Investors \| Investment operations fees
Disaggregation of Revenue [Line Items]
Total revenue	11	0
Institutional Investors \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Total revenue	623	423
Institutional Investors \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Total revenue	1,836	2,088
Institutional Investors \| Professional services fees
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Institutional Investors \| Account fees and other
Disaggregation of Revenue [Line Items]
Total revenue	2,223	2,984
Investments In New Businesses
Disaggregation of Revenue [Line Items]
Total revenue	16,500	14,293
Investments In New Businesses \| United States
Disaggregation of Revenue [Line Items]
Total revenue	15,930	14,293
Investments In New Businesses \| United Kingdom
Disaggregation of Revenue [Line Items]
Total revenue	570	0
Investments In New Businesses \| Canada
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Investments In New Businesses \| Ireland
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Investments In New Businesses \| Luxembourg
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Investments In New Businesses \| Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Total revenue	403	356
Investments In New Businesses \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Total revenue	4,784	4,308
Investments In New Businesses \| Investment operations fees
Disaggregation of Revenue [Line Items]
Total revenue	1,133	1,478
Investments In New Businesses \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Total revenue	9	10
Investments In New Businesses \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Total revenue	5,824	5,097
Investments In New Businesses \| Professional services fees
Disaggregation of Revenue [Line Items]
Total revenue	985	583
Investments In New Businesses \| Account fees and other
Disaggregation of Revenue [Line Items]
Total revenue	$ 3,362	$ 2,461