SECURITIZATIONS AND VARIABLE INTEREST ENTITIES - Asset Based Financing (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Variable Interest Entity
Total unconsolidated VIE assets	$ 419,337,000,000		$ 433,920,000,000
Maximum exposure to unconsolidated VIEs	43,229,000,000		45,937,000,000
Citicorp
Variable Interest Entity
Total unconsolidated VIE assets	375,198,000,000		383,884,000,000
Maximum exposure to unconsolidated VIEs	41,553,000,000		44,156,000,000
Citicorp \| Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	59,289,000,000		61,428,000,000
Maximum exposure to unconsolidated VIEs	25,569,000,000		25,472,000,000
Proceeds from new securitizations	0	500,000,000
Cash flows received on retained interest and other net cash flows	0	0
Citi Holdings
Variable Interest Entity
Total unconsolidated VIE assets	44,139,000,000		50,036,000,000
Maximum exposure to unconsolidated VIEs	1,676,000,000		1,781,000,000
Citi Holdings \| Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	1,165,000,000		1,321,000,000
Maximum exposure to unconsolidated VIEs	123,000,000		126,000,000
Cash flows received on retained interest and other net cash flows	0	100,000,000
Commercial and other real estate \| Citicorp \| Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	25,424,000,000		25,978,000,000
Maximum exposure to unconsolidated VIEs	9,687,000,000		9,426,000,000
Commercial and other real estate \| Citi Holdings \| Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	97,000,000		168,000,000
Maximum exposure to unconsolidated VIEs	50,000,000		50,000,000
Corporate loans \| Citicorp \| Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	587,000,000		460,000,000
Maximum exposure to unconsolidated VIEs	724,000,000		473,000,000
Hedge funds and equities \| Citicorp \| Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	365,000,000		0
Maximum exposure to unconsolidated VIEs	57,000,000		0
Airplanes, ships and other assets \| Citicorp \| Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	32,913,000,000		34,990,000,000
Maximum exposure to unconsolidated VIEs	15,101,000,000		15,573,000,000
Airplanes, ships and other assets \| Citi Holdings \| Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	1,068,000,000		1,153,000,000
Maximum exposure to unconsolidated VIEs	$ 73,000,000		$ 76,000,000

Represents cash flows received on retained interest and other net cash flows.

No definition available.

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- Definition

The amount of involvement with significant unconsolidated Variable Interest Entity assets.

+ References

No definition available.

+ Details

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- Definition

Cash Flows between a transferor and a transferee attributable to newly transferred assets related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=51814546&loc=d3e107207-111719

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph b

-URI http://asc.fasb.org/extlink&oid=52262685&loc=d3e5728-111685

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=52262685&loc=d3e5747-111685

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