RETIREMENT BENEFITS (Details 5) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Amortization of unrecognized
Prior service cost (benefit)		$ (1,000,000)
Defined Contribution Plans
Maximum percentage contribution by employer of employees eligible pay			6.00%	6.00%
Maximum compensation to be eligible for fixed contribution from employer			100,000
Percentage of fixed contribution by employer, for eligible employees whose compensation is $100,000 or less			2.00%
Pretax expense associated with Citigroup 401(k) plan	93,000,000	96,000,000	298,000,000	298,000,000
Postemployment Plans
Postemployment Plans
Benefits earned during the period	0	6,000,000	0	19,000,000
Interest cost on benefit obligation	2,000,000	3,000,000	4,000,000	9,000,000
Amortization of unrecognized
Prior service cost (benefit)	(8,000,000)	1,000,000	(23,000,000)	5,000,000
Net actuarial loss	3,000,000	4,000,000	10,000,000	10,000,000
Total service related expense	(3,000,000)	14,000,000	(9,000,000)	43,000,000
Non-service related expense (benefit)	4,000,000	7,000,000	21,000,000	20,000,000
Total net (benefit) expense	$ 1,000,000	$ 21,000,000	$ 12,000,000	$ 63,000,000