Line of Business Information - Summary of Line of Business (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting Information [Line Items]
Servicing fees	$ 1,259,000,000	$ 1,297,000,000	$ 2,476,000,000	$ 2,665,000,000
Management fees	461,000,000	490,000,000	918,000,000	1,010,000,000
Foreign exchange trading services	303,000,000	331,000,000	645,000,000	690,000,000
Securities finance	117,000,000	107,000,000	226,000,000	203,000,000
Software and processing fees	221,000,000	188,000,000	386,000,000	389,000,000
Other fee revenue	58,000,000	(43,000,000)	103,000,000	(14,000,000)
Total fee revenue	2,419,000,000	2,370,000,000	4,754,000,000	4,943,000,000
Net interest income	691,000,000	584,000,000	1,457,000,000	1,093,000,000
Total other income	0	(1,000,000)	0	(2,000,000)
Total revenue	3,110,000,000	2,953,000,000	6,211,000,000	6,034,000,000
Provision for credit losses	(18,000,000)	10,000,000	26,000,000	10,000,000
Total expenses	2,212,000,000	2,108,000,000	4,581,000,000	4,435,000,000
Income before income tax expense	$ 916,000,000	$ 835,000,000	$ 1,604,000,000	$ 1,589,000,000
Pre-tax margin	29.00%	28.00%	26.00%	26.00%
Operating Segments | Investment Servicing
Segment Reporting Information [Line Items]
Servicing fees	$ 1,259,000,000	$ 1,297,000,000	$ 2,476,000,000	$ 2,665,000,000
Management fees	0	0	0	0
Foreign exchange trading services	276,000,000	313,000,000	597,000,000	655,000,000
Securities finance	109,000,000	102,000,000	212,000,000	195,000,000
Software and processing fees	221,000,000	188,000,000	386,000,000	389,000,000
Other fee revenue	55,000,000	(12,000,000)	83,000,000	34,000,000
Total fee revenue	1,920,000,000	1,888,000,000	3,754,000,000	3,938,000,000
Net interest income	687,000,000	588,000,000	1,449,000,000	1,097,000,000
Total other income	0	(1,000,000)	0	(2,000,000)
Total revenue	2,607,000,000	2,475,000,000	5,203,000,000	5,033,000,000
Provision for credit losses	(18,000,000)	10,000,000	26,000,000	10,000,000
Total expenses	1,850,000,000	1,767,000,000	3,828,000,000	3,692,000,000
Income before income tax expense	$ 775,000,000	$ 698,000,000	$ 1,349,000,000	$ 1,331,000,000
Pre-tax margin	30.00%	28.00%	26.00%	26.00%
Operating Segments | Investment Management
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0	$ 0	$ 0
Management fees	461,000,000	490,000,000	918,000,000	1,010,000,000
Foreign exchange trading services	27,000,000	18,000,000	48,000,000	35,000,000
Securities finance	8,000,000	5,000,000	14,000,000	8,000,000
Software and processing fees	0	0	0	0
Other fee revenue	3,000,000	(31,000,000)	20,000,000	(48,000,000)
Total fee revenue	499,000,000	482,000,000	1,000,000,000	1,005,000,000
Net interest income	4,000,000	(4,000,000)	8,000,000	(4,000,000)
Total other income	0	0	0	0
Total revenue	503,000,000	478,000,000	1,008,000,000	1,001,000,000
Provision for credit losses	0	0	0	0
Total expenses	361,000,000	327,000,000	747,000,000	716,000,000
Income before income tax expense	$ 142,000,000	$ 151,000,000	$ 261,000,000	$ 285,000,000
Pre-tax margin	28.00%	32.00%	26.00%	28.00%
Other
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0	$ 0	$ 0
Management fees	0	0	0	0
Foreign exchange trading services	0	0	0	0
Securities finance	0	0	0	0
Software and processing fees	0	0	0	0
Other fee revenue	0	0		0
Total fee revenue	0	0	0	0
Net interest income	0	0	0	0
Total other income	0	0	0	0
Total revenue	0	0	0	0
Provision for credit losses	0	0	0	0
Total expenses	1,000,000	14,000,000	6,000,000	27,000,000
Income before income tax expense	$ (1,000,000)	$ (14,000,000)	$ (6,000,000)	$ (27,000,000)