PRINCIPAL TRANSACTIONS (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Principal transactions revenue
Principal transactions revenue	$ 7,121	$ 4,781	$ 7,234
Interest rate contracts
Principal transactions revenue
Principal transactions revenue	3,978	2,301	5,136
Foreign exchange contracts
Principal transactions revenue
Principal transactions revenue	2,224	2,403	2,309
Equity contracts
Principal transactions revenue
Principal transactions revenue	319	158	3
Commodity and other contracts
Principal transactions revenue
Principal transactions revenue	267	92	76
Credit derivatives
Principal transactions revenue
Principal transactions revenue	333	(173)	(290)
Citicorp
Principal transactions revenue
Principal transactions revenue	7,097	4,750	5,634
Global Consumer Banking
Principal transactions revenue
Principal transactions revenue	863	812	716
Institutional Clients Group
Principal transactions revenue
Principal transactions revenue	6,310	4,130	4,873
Corporate/Other
Principal transactions revenue
Principal transactions revenue	(76)	(192)	45
Citi Holdings
Principal transactions revenue
Principal transactions revenue	$ 24	$ 31	$ 1,600