Revenues from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Disaggregation of Revenue [Line Items]
Revenues	$ 489,057	$ 481,670	$ 958,176	$ 1,063,113
United States
Disaggregation of Revenue [Line Items]
Revenues	419,412	425,244	819,612	844,873
United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	36,668	24,319	73,609	153,731
Canada
Disaggregation of Revenue [Line Items]
Revenues	11,595	12,447	23,054	25,489
Ireland
Disaggregation of Revenue [Line Items]
Revenues	15,554	15,389	30,684	31,577
Luxembourg
Disaggregation of Revenue [Line Items]
Revenues	5,828	4,160	11,217	7,214
Other
Disaggregation of Revenue [Line Items]
Revenues		111		229
Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Revenues	106,805	115,708	211,378	235,136
Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	104,635	108,299	208,939	223,148
Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	153,050	145,086	300,590	290,825
Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	59,384	56,378	116,969	112,833
Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	35,667	36,777	69,256	73,104
Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	15,319	4,731	20,919	97,849
Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	14,197	14,691	30,125	30,218
Private Banks
Disaggregation of Revenue [Line Items]
Revenues	134,099	124,184	256,702	337,732
Private Banks \| United States
Disaggregation of Revenue [Line Items]
Revenues	91,282	96,115	171,452	177,001
Private Banks \| United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	27,984	13,036	55,830	129,699
Private Banks \| Canada
Disaggregation of Revenue [Line Items]
Revenues	10,148	11,023	20,238	22,823
Private Banks \| Ireland
Disaggregation of Revenue [Line Items]
Revenues	4,685	4,010	9,182	8,209
Private Banks \| Luxembourg
Disaggregation of Revenue [Line Items]
Revenues	0	0	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	32,092	31,993	64,313	65,111
Private Banks \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	824	616	1,310	871
Private Banks \| Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	337	344	683	704
Private Banks \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	56,713	56,378	114,298	112,833
Private Banks \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	28,581	29,845	55,398	59,404
Private Banks \| Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	14,589	4,096	18,675	96,825
Private Banks \| Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	963	912	2,025	1,984
Private Banks \| Professional services fees, one-time early termination fees
Disaggregation of Revenue [Line Items]
Revenues	10,457		10,457	88,000
Investment Advisors
Disaggregation of Revenue [Line Items]
Revenues	109,580	113,194	216,118	232,424
Investment Advisors \| United States
Disaggregation of Revenue [Line Items]
Revenues	109,580	113,194	216,118	232,424
Investment Advisors \| United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investment Advisors \| Canada
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investment Advisors \| Ireland
Disaggregation of Revenue [Line Items]
Revenues	0	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	61,103	67,490	121,708	139,483
Investment Advisors \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	43,159	40,398	83,825	82,406
Investment Advisors \| Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investment Advisors \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	2,296	0	2,296	0
Investment Advisors \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investment Advisors \| Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investment Advisors \| Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	3,022	5,306	8,289	10,535
Institutional Investors
Disaggregation of Revenue [Line Items]
Revenues	75,145	83,483	149,435	170,322
Institutional Investors \| United States
Disaggregation of Revenue [Line Items]
Revenues	63,123	68,702	125,341	139,265
Institutional Investors \| United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	8,684	11,283	17,779	24,032
Institutional Investors \| Canada
Disaggregation of Revenue [Line Items]
Revenues	1,447	1,424	2,816	2,666
Institutional Investors \| Ireland
Disaggregation of Revenue [Line Items]
Revenues	1,891	1,963	3,499	4,130
Institutional Investors \| Luxembourg
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Institutional Investors \| Other
Disaggregation of Revenue [Line Items]
Revenues		111		229
Institutional Investors \| Investment management fees from pooled investment products
Disaggregation of Revenue [Line Items]
Revenues	13,154	15,700	24,437	29,566
Institutional Investors \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	56,627	63,212	115,562	131,672
Institutional Investors \| Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Institutional Investors \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	280	0	280	0
Institutional Investors \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	2,790	3,021	5,441	6,131
Institutional Investors \| Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Institutional Investors \| Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	2,294	1,550	3,715	2,953
Investment Managers
Disaggregation of Revenue [Line Items]
Revenues	165,339	155,926	326,025	312,827
Investment Managers \| United States
Disaggregation of Revenue [Line Items]
Revenues	150,533	142,350	296,805	286,375
Investment Managers \| United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investment Managers \| Canada
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investment Managers \| Ireland
Disaggregation of Revenue [Line Items]
Revenues	8,978	9,416	18,003	19,238
Investment Managers \| Luxembourg
Disaggregation of Revenue [Line Items]
Revenues	5,828	4,160	11,217	7,214
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	104	123	230	207
Investment Managers \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investment Managers \| Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	152,713	144,742	299,907	290,121
Investment Managers \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	75	0	75	0
Investment Managers \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	4,296	3,911	8,417	7,569
Investment Managers \| Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	730	635	2,244	1,024
Investment Managers \| Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	7,421	6,515	15,152	13,906
Investments In New Businesses
Disaggregation of Revenue [Line Items]
Revenues	4,894	4,883	9,896	9,808
Investments In New Businesses \| United States
Disaggregation of Revenue [Line Items]
Revenues	4,894	4,883	9,896	9,808
Investments In New Businesses \| United Kingdom
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investments In New Businesses \| Canada
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investments In New Businesses \| Ireland
Disaggregation of Revenue [Line Items]
Revenues	0	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	352	402	690	769
Investments In New Businesses \| Investment management fees from investment management agreements
Disaggregation of Revenue [Line Items]
Revenues	4,025	4,073	8,242	8,199
Investments In New Businesses \| Investment operations fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investments In New Businesses \| Investment processing fees - PaaS
Disaggregation of Revenue [Line Items]
Revenues	20	0	20	0
Investments In New Businesses \| Investment processing fees - SaaS
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investments In New Businesses \| Professional services fees
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
Investments In New Businesses \| Account fees and other
Disaggregation of Revenue [Line Items]
Revenues	$ 497	$ 408	$ 944	$ 840