BORROWED FUNDS - Maturities of Long-term Borrowed Funds (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
2022	$ 172
2023	9,002
2024	107
2025	1,878
2026	989
2027 and thereafter	2,292
Total	14,440	$ 6,932
Parent Company
Debt Instrument [Line Items]
2022	168
2023	0
2024	107
2025	469
2026	498
2027 and thereafter	2,272
Total	3,514
CBNA and Other Subsidiaries
Debt Instrument [Line Items]
2022	4
2023	9,002
2024	0
2025	1,409
2026	491
2027 and thereafter	20
Total	$ 10,926

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