GUARANTEES, LEASES AND COMMITMENTS - Credit Commitments and Lines of Credit (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Guarantor Obligations
Credit commitments	$ 1,049,411	$ 1,062,781
Unsettled reverse repurchase and securities borrowing agreements	130,900	126,600
Unsettled repurchase and securities lending agreements	59,400	41,100
Commercial and similar letters of credit
Guarantor Obligations
Credit commitments	6,572	5,910
One- to four-family residential mortgages
Guarantor Obligations
Credit commitments	3,740	4,351
Revolving open-end loans secured by one- to four-family residential properties
Guarantor Obligations
Credit commitments	6,975	7,913
Commercial real estate, construction and land development
Guarantor Obligations
Credit commitments	17,713	17,843
Credit card lines
Guarantor Obligations
Credit commitments	700,956	700,559
Commercial and other consumer loan commitments
Guarantor Obligations
Credit commitments	308,008	320,556
Other commitments and contingencies
Guarantor Obligations
Credit commitments	5,447	$ 5,649
U.S.
Guarantor Obligations
Credit commitments	838,330
U.S. | Commercial and similar letters of credit
Guarantor Obligations
Credit commitments	732
U.S. | One- to four-family residential mortgages
Guarantor Obligations
Credit commitments	2,048
U.S. | Revolving open-end loans secured by one- to four-family residential properties
Guarantor Obligations
Credit commitments	6,280
U.S. | Commercial real estate, construction and land development
Guarantor Obligations
Credit commitments	15,402
U.S. | Credit card lines
Guarantor Obligations
Credit commitments	608,097
U.S. | Commercial and other consumer loan commitments
Guarantor Obligations
Credit commitments	200,543
U.S. | Other commitments and contingencies
Guarantor Obligations
Credit commitments	5,228
Outside of U.S.
Guarantor Obligations
Credit commitments	211,081
Outside of U.S. | Commercial and similar letters of credit
Guarantor Obligations
Credit commitments	5,840
Outside of U.S. | One- to four-family residential mortgages
Guarantor Obligations
Credit commitments	1,692
Outside of U.S. | Revolving open-end loans secured by one- to four-family residential properties
Guarantor Obligations
Credit commitments	695
Outside of U.S. | Commercial real estate, construction and land development
Guarantor Obligations
Credit commitments	2,311
Outside of U.S. | Credit card lines
Guarantor Obligations
Credit commitments	92,859
Outside of U.S. | Commercial and other consumer loan commitments
Guarantor Obligations
Credit commitments	107,465
Outside of U.S. | Other commitments and contingencies
Guarantor Obligations
Credit commitments	$ 219