DEBT - Maturities of Long-term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument
2024	$ 45,788
2025	46,424
2026	40,380
2027	21,262
2028	30,114
Thereafter	102,651
Total	286,619	$ 271,606
Bank
Debt Instrument
2024	11,798
2025	10,415
2026	3,183
2027	774
2028	3,679
Thereafter	1,824
Total	31,673
Broker-dealer
Debt Instrument
2024	26,955
2025	17,117
2026	8,202
2027	7,117
2028	7,644
Thereafter	25,602
Total	92,637
Citigroup Inc.
Debt Instrument
2024	7,035
2025	18,892
2026	28,995
2027	13,371
2028	18,791
Thereafter	75,225
Total	$ 162,309	$ 166,257

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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