BORROWED FUNDS - Maturities of Long-term Borrowed Funds (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
2022	$ 923
2023	758
2024	108
2025	1,229
2026	997
2027 and thereafter	1,879
Total	5,894	$ 6,932
Parent Company
Debt Instrument [Line Items]
2022	168
2023	0
2024	107
2025	469
2026	498
2027 and thereafter	1,859
Total	3,101
CBNA and Other Subsidiaries
Debt Instrument [Line Items]
2022	755
2023	758
2024	1
2025	760
2026	499
2027 and thereafter	20
Total	$ 2,793

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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