DEBT - Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument
Weighted average interest rate	2.94%
Long-term debt	$ 254,374	$ 271,686
Weighted average interest rate after effect of derivative contract	3.12%
Senior debt
Debt Instrument
Long-term debt	$ 226,870	242,835
Subordinated debt
Debt Instrument
Long-term debt	25,770	27,121
Trust preferred securities
Debt Instrument
Long-term debt	1,734	1,730
Citigroup Inc.
Debt Instrument
Long-term debt	$ 164,945
Citigroup Inc. \| Senior debt
Debt Instrument
Weighted average interest rate	2.88%
Long-term debt	$ 137,651	142,197
Citigroup Inc. \| Subordinated debt
Debt Instrument
Weighted average interest rate	4.65%
Long-term debt	$ 25,560	26,636
Citigroup Inc. \| Trust preferred securities
Debt Instrument
Weighted average interest rate	6.30%
Long-term debt	$ 1,734	1,730
Bank
Debt Instrument
Long-term debt	$ 23,567
Bank \| Senior debt
Debt Instrument
Weighted average interest rate	1.54%
Long-term debt	$ 23,567	44,742
Collateralized long-term advances from Federal Home Loan Bank	5,300	10,900
Broker-dealer
Debt Instrument
Long-term debt	$ 65,862
Broker-dealer \| Senior debt
Debt Instrument
Weighted average interest rate	0.84%
Long-term debt	$ 65,652	55,896
Broker-dealer \| Subordinated debt
Debt Instrument
Weighted average interest rate	0.00%
Long-term debt	$ 210	$ 485

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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, 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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