DEBT - Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument
Weighted average interest rate	3.72%
Long-term debt	$ 271,606	$ 254,374
Weighted average interest rate after effect of derivative contract	4.10%
Senior debt
Debt Instrument
Long-term debt	$ 247,242	227,080
Subordinated debt
Debt Instrument
Long-term debt	22,758	25,560
Trust preferred securities
Debt Instrument
Long-term debt	1,606	1,734
Citigroup Inc.
Debt Instrument
Long-term debt	$ 166,257
Citigroup Inc. \| Senior debt
Debt Instrument
Weighted average interest rate	3.38%
Long-term debt	$ 141,893	137,651
Citigroup Inc. \| Subordinated debt
Debt Instrument
Weighted average interest rate	4.77%
Long-term debt	$ 22,758	25,560
Citigroup Inc. \| Trust preferred securities
Debt Instrument
Weighted average interest rate	10.53%
Long-term debt	$ 1,606	1,734
Bank
Debt Instrument
Long-term debt	$ 21,113
Bank \| Senior debt
Debt Instrument
Weighted average interest rate	3.98%
Long-term debt	$ 21,113	23,567
Collateralized long-term advances from Federal Home Loan Bank	7,300	5,300
Broker-dealer
Debt Instrument
Long-term debt	$ 84,236
Broker-dealer \| Senior debt
Debt Instrument
Weighted average interest rate	3.95%
Long-term debt	$ 84,236	$ 65,862

Represents the weighted average interest rate at the end of the period after the effect of the derivative contract.

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- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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