SECURITIZATIONS AND VARIABLE INTEREST ENTITIES - Funding, Liquidity Facilities and Subordinated Interests (Details) $ in Billions	12 Months Ended
Dec. 31, 2021 USD ($) trust	Dec. 31, 2020 USD ($)
Funding, Liquidity Facilities and Subordinated Interests
Number of trusts to hold securitized credit card receivables \| trust	2
Citibank Credit Card Master Trust (Master Trust)
Funding, Liquidity Facilities and Subordinated Interests
Weighted average maturity of term notes	3 years 7 months 6 days	2 years 10 months 24 days
Term notes issued to third parties	$ 8.4	$ 13.9
Term notes retained by Citigroup affiliates	2.2	2.7
Total Trust liabilities	$ 10.6	$ 16.6
Citibank OMNI Master Trust (Omni Trust)
Funding, Liquidity Facilities and Subordinated Interests
Weighted average maturity of term notes	1 year 7 months 6 days	1 year 1 month 6 days
Term notes issued to third parties	$ 1.3	$ 1.8
Term notes retained by Citigroup affiliates	5.0	5.2
Total Trust liabilities	$ 6.3	$ 7.0

No definition available.

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The par value of liabilities of the credit card receivables securitization trust.

No definition available.

Represents the number of securitization trusts established to hold in trust a specific type of securitized receivables.

No definition available.

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The par value of liabilities of the credit card receivables securitization trust related to term notes issued to third parties.

No definition available.

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The par value of liabilities of the credit card receivables securitization trust related to term notes retained by affiliates of the entity.

No definition available.

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This element represents the weighted average maturity of the term notes.

No definition available.

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