LOANS (Details 6) (USD $)	3 Months Ended			9 Months Ended			12 Months Ended
	Sep. 30, 2014		Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013	Dec. 31, 2013
Loans receivable
Loans, net of unearned income	$ 653,826,000,000			$ 653,826,000,000			$ 665,472,000,000
Loans at fair value	4,411,000,000			4,411,000,000			5,029,000,000
Corporate
Loans receivable
Loans sold and/or reclassified to held-for-sale	1,700,000,000		1,800,000,000	4,200,000,000		4,000,000,000
Number of days past due for reversal of accrued interest and charging to earnings				90 days		90 days
Loans, equal to 30- 89 days past due and accruing	378,000,000	[1]		378,000,000	[1]		311,000,000	[1]
Loans, greater than or equal to 90 days past due and accruing	97,000,000	[1]		97,000,000	[1]		183,000,000	[1]
Loans, total Past due and accruing	475,000,000			475,000,000			494,000,000
Loans, total non-accrual	1,350,000,000	[2]		1,350,000,000	[2]		1,908,000,000	[2]
Loans, total current	271,317,000,000	[3]		271,317,000,000	[3]		265,167,000,000	[3]
Loans, net of unearned income	277,508,000,000	[4]		277,508,000,000	[4]		271,641,000,000	[4]
Loans at fair value	4,366,000,000	[4]		4,366,000,000	[4]		4,072,000,000	[4]
Number of days past due, non-accrual status				90 days			90 days
Loans less than this number of days past due are considered current				30 days			30 days
Corporate | Commercial and industrial
Loans receivable
Loans, equal to 30- 89 days past due and accruing	212,000,000	[1]		212,000,000	[1]		72,000,000	[1]
Loans, greater than or equal to 90 days past due and accruing	1,000,000	[1]		1,000,000	[1]		5,000,000	[1]
Loans, total Past due and accruing	213,000,000			213,000,000			77,000,000
Loans, total non-accrual	733,000,000	[2]		733,000,000	[2]		769,000,000	[2]
Loans, total current	113,211,000,000	[3]		113,211,000,000	[3]		112,985,000,000	[3]
Loans, net of unearned income	114,157,000,000	[4]		114,157,000,000	[4]		113,831,000,000	[4]
Corporate | Financial institutions
Loans receivable
Loans, equal to 30- 89 days past due and accruing	5,000,000	[1]		5,000,000	[1]		0	[1]
Loans, greater than or equal to 90 days past due and accruing	0	[1]		0	[1]
Loans, total Past due and accruing	5,000,000			5,000,000			0
Loans, total non-accrual	266,000,000	[2]		266,000,000	[2]		365,000,000	[2]
Loans, total current	66,226,000,000	[3]		66,226,000,000	[3]		61,704,000,000	[3]
Loans, net of unearned income	66,497,000,000	[4]		66,497,000,000	[4]		62,069,000,000	[4]
Corporate | Mortgage and real estate
Loans receivable
Loans, equal to 30- 89 days past due and accruing	100,000,000	[1]		100,000,000	[1]		183,000,000	[1]
Loans, greater than or equal to 90 days past due and accruing	94,000,000	[1]		94,000,000	[1]		175,000,000	[1]
Loans, total Past due and accruing	194,000,000			194,000,000			358,000,000
Loans, total non-accrual	237,000,000	[2]		237,000,000	[2]		515,000,000	[2]
Loans, total current	37,935,000,000	[3]		37,935,000,000	[3]		34,027,000,000	[3]
Loans, net of unearned income	38,366,000,000	[4]		38,366,000,000	[4]		34,900,000,000	[4]
Corporate | Leases
Loans receivable
Loans, equal to 30- 89 days past due and accruing	4,000,000	[1]		4,000,000	[1]		9,000,000	[1]
Loans, greater than or equal to 90 days past due and accruing	0	[1]		0	[1]		1,000,000	[1]
Loans, total Past due and accruing	4,000,000			4,000,000			10,000,000
Loans, total non-accrual	49,000,000	[2]		49,000,000	[2]		189,000,000	[2]
Loans, total current	2,080,000,000	[3]		2,080,000,000	[3]		1,975,000,000	[3]
Loans, net of unearned income	2,133,000,000	[4]		2,133,000,000	[4]		2,174,000,000	[4]
Corporate | Other
Loans receivable
Loans, equal to 30- 89 days past due and accruing	57,000,000	[1]		57,000,000	[1]		47,000,000	[1]
Loans, greater than or equal to 90 days past due and accruing	2,000,000	[1]		2,000,000	[1]		2,000,000	[1]
Loans, total Past due and accruing	59,000,000			59,000,000			49,000,000
Loans, total non-accrual	65,000,000	[2]		65,000,000	[2]		70,000,000	[2]
Loans, total current	51,865,000,000	[3]		51,865,000,000	[3]		54,476,000,000	[3]
Loans, net of unearned income	$ 51,989,000,000	[4]		$ 51,989,000,000	[4]		$ 54,595,000,000	[4]

[1] Corporate loans that are 90 days past due are generally classified as non-accrual. Corporate loans are considered past due when principal or interest is contractually due but unpaid.

[2] Citi generally does not manage corporate loans on a delinquency basis. Non-accrual loans generally include those loans that are ≥ 90 days past due or those loans for which Citi believes, based on actual experience and a forward-looking assessment of the collectability of the loan in full, that the payment of interest or principal is doubtful.

[3] Corporate loans are past due when principal or interest is contractually due but unpaid. Loans less than 30 days past due are presented as current.

[4] Total loans include loans at fair value, which are not included in the various delinquency columns.