GUARANTEES AND COMMITMENTS - Credit Commitments and Lines of Credit (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Guarantor Obligations
Credit commitments	$ 1,030,559	$ 1,015,564
Unsettled reverse repurchase and securities borrowing agreements	150,400	111,600
Unsettled repurchase and securities lending agreements	117,500	37,300
Commercial and similar letters of credit
Guarantor Obligations
Credit commitments	4,869	5,316
One- to four-family residential mortgages
Guarantor Obligations
Credit commitments	2,577	2,394
Revolving open-end loans secured by one- to four-family residential properties
Guarantor Obligations
Credit commitments	6,324	6,380
Commercial real estate, construction and land development
Guarantor Obligations
Credit commitments	14,995	15,170
Credit card lines
Guarantor Obligations
Credit commitments	688,649	683,232
Commercial and other consumer loan commitments
Guarantor Obligations
Credit commitments	307,540	297,399
Other commitments and contingencies
Guarantor Obligations
Credit commitments	5,605	$ 5,673
UNITED STATES
Guarantor Obligations
Credit commitments	837,940
UNITED STATES | Commercial and similar letters of credit
Guarantor Obligations
Credit commitments	457
UNITED STATES | One- to four-family residential mortgages
Guarantor Obligations
Credit commitments	1,728
UNITED STATES | Revolving open-end loans secured by one- to four-family residential properties
Guarantor Obligations
Credit commitments	5,656
UNITED STATES | Commercial real estate, construction and land development
Guarantor Obligations
Credit commitments	13,399
UNITED STATES | Credit card lines
Guarantor Obligations
Credit commitments	612,136
UNITED STATES | Commercial and other consumer loan commitments
Guarantor Obligations
Credit commitments	199,231
UNITED STATES | Other commitments and contingencies
Guarantor Obligations
Credit commitments	5,333
In offices outside North America
Guarantor Obligations
Credit commitments	192,619
In offices outside North America | Commercial and similar letters of credit
Guarantor Obligations
Credit commitments	4,412
In offices outside North America | One- to four-family residential mortgages
Guarantor Obligations
Credit commitments	849
In offices outside North America | Revolving open-end loans secured by one- to four-family residential properties
Guarantor Obligations
Credit commitments	668
In offices outside North America | Commercial real estate, construction and land development
Guarantor Obligations
Credit commitments	1,596
In offices outside North America | Credit card lines
Guarantor Obligations
Credit commitments	76,513
In offices outside North America | Commercial and other consumer loan commitments
Guarantor Obligations
Credit commitments	108,309
In offices outside North America | Other commitments and contingencies
Guarantor Obligations
Credit commitments	$ 272