DEBT - Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Debt Instrument
Weighted average interest rate	4.29%
Long-term debt	$ 315,827	$ 287,300
Weighted average interest rate after effect of derivative contract	4.36%
Senior debt
Debt Instrument
Long-term debt	$ 285,126	256,795
Subordinated debt
Debt Instrument
Long-term debt	29,068	28,883
Trust preferred securities
Debt Instrument
Long-term debt	1,633	1,622
Citigroup Inc.
Debt Instrument
Long-term debt	$ 177,855	164,024
Citigroup Inc. \| Senior debt
Debt Instrument
Weighted average interest rate	3.91%
Long-term debt	$ 147,154	133,519
Citigroup Inc. \| Subordinated debt
Debt Instrument
Weighted average interest rate	5.21%
Long-term debt	$ 29,068	28,883
Citigroup Inc. \| Trust preferred securities
Debt Instrument
Weighted average interest rate	10.24%
Long-term debt	$ 1,633	1,622
Bank
Debt Instrument
Long-term debt	$ 36,481
Bank \| Senior debt
Debt Instrument
Weighted average interest rate	4.55%
Long-term debt	$ 36,481	35,470
Collateralized long-term advances from Federal Home Loan Bank	3,000	8,500
Broker-dealer
Debt Instrument
Long-term debt	$ 101,491
Broker-dealer \| Senior debt
Debt Instrument
Weighted average interest rate	4.25%
Long-term debt	$ 101,491	$ 87,806

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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- Definition

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

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