SECURITIZATIONS AND VARIABLE INTEREST ENTITIES - Funding, Liquidity Facilities and Subordinated Interests (Details) $ in Billions	12 Months Ended
Dec. 31, 2017 USD ($) trust	Dec. 31, 2016 USD ($)
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	2 years 6 months 25 days	2 years 6 months 25 days
Term notes issued to third parties	$ 27.8	$ 21.7
Term notes retained by Citigroup affiliates	5.7	5.5
Total Trust liabilities	$ 33.5	$ 27.2
Citibank OMNI Master Trust (Omni Trust)
Funding, Liquidity Facilities and Subordinated Interests
Weighted average maturity of term notes	1 year 11 months	1 year 11 months
Term notes issued to third parties	$ 1.0	$ 1.0
Term notes retained by Citigroup affiliates	1.9	1.9
Total Trust liabilities	$ 2.9	$ 2.9

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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