BORROWED FUNDS - Maturities of Long-term Borrowed Funds (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
2022	$ 2
2023	7,000
2024	3,357
2025	1,878
2026	972
2027 and thereafter	3,077
Total	16,286	$ 6,932
Parent Company
Debt Instrument [Line Items]
2022	0
2023	0
2024	106
2025	469
2026	498
2027 and thereafter	2,260
Total	3,333
CBNA and Other Subsidiaries
Debt Instrument [Line Items]
2022	2
2023	7,000
2024	3,251
2025	1,409
2026	474
2027 and thereafter	817
Total	$ 12,953

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