SECURITIZATIONS AND VARIABLE INTEREST ENTITIES (Details 8) (USD $)			3 Months Ended		9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 Asset-based financing	Sep. 30, 2011 Asset-based financing	Sep. 30, 2012 Asset-based financing	Sep. 30, 2011 Asset-based financing	Sep. 30, 2012 Citicorp	Dec. 31, 2011 Citicorp	Sep. 30, 2012 Citicorp Asset-based financing	Sep. 30, 2012 Citi Holdings	Dec. 31, 2011 Citi Holdings	Sep. 30, 2012 Citi Holdings Asset-based financing	Sep. 30, 2012 Commercial and other real estate Citicorp Asset-based financing	Sep. 30, 2012 Commercial and other real estate Citi Holdings Asset-based financing	Sep. 30, 2012 Hedge funds and equities Citicorp Asset-based financing	Sep. 30, 2012 Corporate loans Citi Holdings Asset-based financing	Sep. 30, 2012 Airplanes, ships and other assets Citicorp Asset-based financing	Sep. 30, 2012 Airplanes, ships and other assets Citi Holdings Asset-based financing
Variable Interest Entity
Total unconsolidated VIE assets	$ 500,365,000,000	$ 553,237,000,000					$ 338,177,000,000	$ 348,138,000,000	$ 25,800,000,000	$ 162,188,000,000	$ 205,099,000,000	$ 7,900,000,000	$ 8,900,000,000	$ 1,400,000,000	$ 600,000,000	$ 2,900,000,000	$ 16,300,000,000	$ 3,600,000,000
Maximum exposure to unconsolidated VIEs	45,710,000,000	53,422,000,000					39,209,000,000	43,748,000,000	15,000,000,000	6,501,000,000	9,674,000,000	3,400,000,000	2,200,000,000	400,000,000	400,000,000	2,300,000,000	12,400,000,000	700,000,000
Cash flows received on retained interest and other net cash flows			$ 400,000,000	$ 200,000,000	$ 1,700,000,000	$ 1,200,000,000