Revenues from Contracts with Customers (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Revenues	$ 1,919,793	$ 1,991,037	$ 1,918,309
United States
Disaggregation of Revenue [Line Items]
Revenues	1,640,109	1,623,022	1,629,527
United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	147,800	242,071	165,788
Canada
Disaggregation of Revenue [Line Items]
Revenues	45,626	48,419	52,721
Ireland
Disaggregation of Revenue [Line Items]
Revenues	62,524	60,365	69,770
Luxembourg
Disaggregation of Revenue [Line Items]
Revenues	23,734	16,898
Other
Disaggregation of Revenue [Line Items]
Revenues		262	503
Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Revenues	416,358	445,224	495,378
Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	417,368	432,322	458,087
Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	618,401	579,813	539,958
Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	254,304	234,278	223,009
Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	117,456	139,102	128,963
Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	31,375	104,842	25,562
Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	64,531	55,456	47,352
Private Banks
Disaggregation of Revenue [Line Items]
Revenues	503,317	575,625	493,570
Private Banks \| United States
Disaggregation of Revenue [Line Items]
Revenues	332,543	317,399	315,040
Private Banks \| United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	113,221	199,294	111,900
Private Banks \| Canada
Disaggregation of Revenue [Line Items]
Revenues	39,974	43,108	48,325
Private Banks \| Ireland
Disaggregation of Revenue [Line Items]
Revenues	17,579	15,824	18,305
Private Banks \| Luxembourg
Disaggregation of Revenue [Line Items]
Revenues	0	0
Private Banks \| Other
Disaggregation of Revenue [Line Items]
Revenues		0	0
Private Banks \| Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Revenues	127,388	125,430	134,617
Private Banks \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	3,091	2,187	2,271
Private Banks \| Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	1,572	1,410	1,512
Private Banks \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	248,926	228,556	215,473
Private Banks \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	90,150	112,096	113,964
Private Banks \| Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	28,069	102,169	22,054
Private Banks \| Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	4,121	3,777	3,679
Private Banks \| Professional services fees, one-time early termination fees
Disaggregation of Revenue [Line Items]
Revenues	10,457	88,000
Investment Advisors
Disaggregation of Revenue [Line Items]
Revenues	436,298	447,766	482,949
Investment Advisors \| United States
Disaggregation of Revenue [Line Items]
Revenues	436,298	447,766	482,949
Investment Advisors \| United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investment Advisors \| Canada
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investment Advisors \| Ireland
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investment Advisors \| Luxembourg
Disaggregation of Revenue [Line Items]
Revenues	0	0
Investment Advisors \| Other
Disaggregation of Revenue [Line Items]
Revenues		0	0
Investment Advisors \| Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Revenues	239,244	263,266	301,581
Investment Advisors \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	174,418	162,762	158,181
Investment Advisors \| Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investment Advisors \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	4,635	5,100	6,907
Investment Advisors \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investment Advisors \| Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investment Advisors \| Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	18,001	16,638	16,280
Institutional Investors
Disaggregation of Revenue [Line Items]
Revenues	289,708	323,353	343,805
Institutional Investors \| United States
Disaggregation of Revenue [Line Items]
Revenues	242,945	267,928	274,867
Institutional Investors \| United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	34,485	42,777	53,888
Institutional Investors \| Canada
Disaggregation of Revenue [Line Items]
Revenues	5,652	5,311	4,396
Institutional Investors \| Ireland
Disaggregation of Revenue [Line Items]
Revenues	6,626	7,075	10,151
Institutional Investors \| Luxembourg
Disaggregation of Revenue [Line Items]
Revenues	0	0
Institutional Investors \| Other
Disaggregation of Revenue [Line Items]
Revenues		262	503
Institutional Investors \| Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Revenues	47,943	54,656	57,716
Institutional Investors \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	223,212	251,256	282,797
Institutional Investors \| Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Institutional Investors \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	457	396	308
Institutional Investors \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	10,118	11,425	1,207
Institutional Investors \| Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Institutional Investors \| Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	7,978	5,620	1,777
Investment Managers
Disaggregation of Revenue [Line Items]
Revenues	670,486	624,918	581,157
Investment Managers \| United States
Disaggregation of Revenue [Line Items]
Revenues	608,339	570,554	539,843
Investment Managers \| United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	94	0	0
Investment Managers \| Canada
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investment Managers \| Ireland
Disaggregation of Revenue [Line Items]
Revenues	38,319	37,466	41,314
Investment Managers \| Luxembourg
Disaggregation of Revenue [Line Items]
Revenues	23,734	16,898
Investment Managers \| Other
Disaggregation of Revenue [Line Items]
Revenues		0	0
Investment Managers \| Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Revenues	401	396	134
Investment Managers \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investment Managers \| Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	616,829	578,403	538,446
Investment Managers \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	244	186	300
Investment Managers \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	17,188	15,581	13,792
Investment Managers \| Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	3,306	2,673	3,508
Investment Managers \| Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	32,518	27,679	24,977
Investments in New Businesses
Disaggregation of Revenue [Line Items]
Revenues	19,984	19,375	16,828
Investments in New Businesses \| United States
Disaggregation of Revenue [Line Items]
Revenues	19,984	19,375	16,828
Investments in New Businesses \| United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investments in New Businesses \| Canada
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investments in New Businesses \| Ireland
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investments in New Businesses \| Luxembourg
Disaggregation of Revenue [Line Items]
Revenues	0	0
Investments in New Businesses \| Other
Disaggregation of Revenue [Line Items]
Revenues		0	0
Investments in New Businesses \| Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Revenues	1,382	1,476	1,330
Investments in New Businesses \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	16,647	16,117	14,838
Investments in New Businesses \| Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investments in New Businesses \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	42	40	21
Investments in New Businesses \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investments in New Businesses \| Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0
Investments in New Businesses \| Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	$ 1,913	$ 1,742	$ 639