CONTINGENCIES (Details) (USD $)				3 Months Ended		3 Months Ended	0 Months Ended		3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Apr. 30, 2013 Case from US Bank [Member] loan	Mar. 31, 2013 Residential Mortgage-Backed Securities Investor Actions and Repurchase Claims In Re Citigroup Inc. Securities Litigation	Mar. 25, 2013 Residential Mortgage-Backed Securities Investor Actions and Repurchase Claims In Re Citigroup Inc. Securities Litigation	Mar. 31, 2013 KIKOs CKI item	Mar. 05, 2013 Auction Rate Securities-Related Litigation and Other Matters item	Mar. 28, 2013 Terra Firma Litigation item	Mar. 31, 2013 Interbank Offered Rates-Related Litigation and Other Matters item
CONTINGENCIES
Possible loss, high end of the range	$ 5,000,000,000	$ 5,000,000,000
Contingencies
Settlement agreement consideration					730,000,000
Aggregate original purchase amount				12,000,000,000
Aggregate original purchase amount of the purchases covered by tolling agreements				6,000,000,000
Number of putative class actions dismissed							2
Number of putative class actions against entity (in lawsuit)									3
Number of decision rendered at district court level						83
Decisions favorable to entity						64
Number of decisions awarded to plaintiff for portion of damages sought						19
Contingent loss as claimed against the company						28,900,000
Number of decisions appealed at the high court						61
Number of cases decided at the high court						21
Number of decisions favorable to the entity in the high court						13
Number of decisions awarded by the high court to the plaintiff for a portion of damages sought						8
Increase in damages awarded						$ 10,200,000
Number civil lawsuits filed by small and medium-sized enterprises						90
Number of decisions appealed at the Supreme court						6
Number of plaintiffs								7
Minimum number of securitized loans claimed to enforce contractual repurchase			1,267