COMMISSIONS AND FEES; ADMINISTRATION AND OTHER FIDUCIARY FEES - Administration and Other Fiduciary Fees (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Commissions and fees
Administration and other fiduciary fees	$ 3,781	$ 3,784	$ 3,943
Custody fees
Commissions and fees
Administration and other fiduciary fees	1,871	1,877	1,898
Fiduciary fees
Commissions and fees
Administration and other fiduciary fees	1,376	1,350	1,464
Guarantee fees
Commissions and fees
Administration and other fiduciary fees	534	557	581
Administration and other fiduciary fees
Commissions and fees
Administration and other fiduciary fees	3,781	3,784	3,943
Revenue not accounted for under ASC 606	$ 534	$ 557	$ 581