Line of Business Information - Summary of Line of Business (Details) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Servicing fees	$ 1,217,000,000	$ 1,368,000,000
Management fees	457,000,000	520,000,000
Foreign exchange trading services	342,000,000	359,000,000
Securities finance	109,000,000	96,000,000
Software and processing fees	165,000,000	201,000,000
Other fee revenue	45,000,000	29,000,000
Total fee revenue	2,335,000,000	2,573,000,000
Net interest income	766,000,000	509,000,000
Total other income	0	(1,000,000)
Total revenue	3,101,000,000	3,081,000,000
Provision for credit losses	44,000,000	0
Total expenses	2,369,000,000	2,327,000,000
Income before income tax expense	$ 688,000,000	$ 754,000,000
Pre-tax margin	22.00%	24.00%
Operating Segments | Investment Servicing
Segment Reporting Information [Line Items]
Servicing fees	$ 1,217,000,000	$ 1,368,000,000
Management fees	0	0
Foreign exchange trading services	321,000,000	342,000,000
Securities finance	103,000,000	93,000,000
Software and processing fees	165,000,000	201,000,000
Other fee revenue	28,000,000	46,000,000
Total fee revenue	1,834,000,000	2,050,000,000
Net interest income	762,000,000	509,000,000
Total other income	0	(1,000,000)
Total revenue	2,596,000,000	2,558,000,000
Provision for credit losses	44,000,000	0
Total expenses	1,978,000,000	1,925,000,000
Income before income tax expense	$ 574,000,000	$ 633,000,000
Pre-tax margin	22.00%	25.00%
Operating Segments | Investment Management
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0
Management fees	457,000,000	520,000,000
Foreign exchange trading services	21,000,000	17,000,000
Securities finance	6,000,000	3,000,000
Software and processing fees	0	0
Other fee revenue	17,000,000	(17,000,000)
Total fee revenue	501,000,000	523,000,000
Net interest income	4,000,000	0
Total other income	0	0
Total revenue	505,000,000	523,000,000
Provision for credit losses	0	0
Total expenses	386,000,000	389,000,000
Income before income tax expense	$ 119,000,000	$ 134,000,000
Pre-tax margin	24.00%	26.00%
Other
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0
Management fees	0	0
Foreign exchange trading services	0	0
Securities finance	0	0
Software and processing fees	0	0
Other fee revenue	0	0
Total fee revenue	0	0
Net interest income	0	0
Total other income	0	0
Total revenue	0	0
Provision for credit losses	0	0
Total expenses	5,000,000	13,000,000
Income before income tax expense	$ (5,000,000)	$ (13,000,000)