LOANS (Details 3) (USD $)	3 Months Ended				6 Months Ended				12 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013		Dec. 31, 2013
Financing receivable impaired
Maximum period of loan modification under Citi's short-term modification programs					12 months
Loans individually evaluated for impairment in accordance with ASC 310-10-35	$ 23,743,000,000				$ 23,743,000,000				$ 26,015,000,000
Number of quarters used to calculate the average recorded investment balance	4				4				4
Consumer
Financing receivable impaired
Recorded investment									23,793,000,000	[1],[2],[3]
Unpaid principal balance	24,123,000,000	[4]			24,123,000,000	[4]			25,727,000,000	[3]
Related specific allowance	4,400,000,000	[4],[5]			4,400,000,000	[4],[5]			4,633,000,000	[3],[5]
Average carrying value					23,417,000,000	[4],[6]			24,950,000,000	[3],[7]
Interest income recognized	283,000,000	[4],[8],[9]	328,000,000	[4],[8],[9]	582,000,000	[4],[8],[9]	684,000,000	[4],[8],[9]
Smaller-balance impaired consumer loans modified since January 1, 2008, dollar amount	21,900,000,000				21,900,000,000				23,400,000,000
Amounts of such outstanding modified consumer loans, including those modified prior to 2008	22,500,000,000				22,500,000,000				24,000,000,000
Consumer | Residential First Mortgage Loans
Financing receivable impaired
Recorded investment	15,965,000,000	[10],[2]			15,965,000,000	[10],[2]			16,801,000,000	[1],[2]
Unpaid principal balance	16,962,000,000				16,962,000,000				17,788,000,000
Related specific allowance	2,215,000,000	[5]			2,215,000,000	[5]			2,309,000,000	[5]
Average carrying value					16,660,000,000	[6]			17,616,000,000	[7]
Interest income recognized	181,000,000	[8],[9]	207,000,000	[8],[9]	365,000,000	[8],[9]	424,000,000	[8],[9]
Impaired financing receivable without specific allowance	2,106,000,000				2,106,000,000				2,169,000,000
Consumer | Home equity loans
Financing receivable impaired
Recorded investment	2,087,000,000	[10],[2]			2,087,000,000	[10],[2]			2,141,000,000	[1],[2]
Unpaid principal balance	2,729,000,000				2,729,000,000				2,806,000,000
Related specific allowance	562,000,000	[5]			562,000,000	[5]			427,000,000	[5]
Average carrying value					2,147,000,000	[6]			2,116,000,000	[7]
Interest income recognized	19,000,000	[8],[9]	18,000,000	[8],[9]	38,000,000	[8],[9]	39,000,000	[8],[9]
Impaired financing receivable without specific allowance	564,000,000				564,000,000				568,000,000
Consumer | Credit cards
Financing receivable impaired
Recorded investment	2,826,000,000	[10],[2]			2,826,000,000	[10],[2]			3,339,000,000	[1],[2]
Unpaid principal balance	2,868,000,000				2,868,000,000				3,385,000,000
Related specific allowance	965,000,000	[5]			965,000,000	[5]			1,178,000,000	[5]
Average carrying value					3,192,000,000	[6]			3,720,000,000	[7]
Interest income recognized	50,000,000	[8],[9]	61,000,000	[8],[9]	101,000,000	[8],[9]	126,000,000	[8],[9]
Consumer | Individual installment and other
Financing receivable impaired
Recorded investment	986,000,000	[10],[2]			986,000,000	[10],[2]			1,114,000,000	[1],[2]
Unpaid principal balance	999,000,000				999,000,000				1,143,000,000
Related specific allowance	476,000,000	[5]			476,000,000	[5]			536,000,000	[5]
Average carrying value					1,043,000,000	[6]			1,094,000,000	[7]
Interest income recognized	29,000,000	[8],[9]	34,000,000	[8],[9]	63,000,000	[8],[9]	83,000,000	[8],[9]
Consumer | Commercial market loans
Financing receivable impaired
Recorded investment	367,000,000	[10],[2]			367,000,000	[10],[2]			398,000,000	[1],[2]
Unpaid principal balance	565,000,000				565,000,000				605,000,000
Related specific allowance	182,000,000	[5]			182,000,000	[5]			183,000,000	[5]
Average carrying value					375,000,000	[6]			404,000,000	[7]
Interest income recognized	4,000,000	[8],[9]	8,000,000	[8],[9]	15,000,000	[8],[9]	12,000,000	[8],[9]
Impaired financing receivable without specific allowance	$ 86,000,000				$ 86,000,000				$ 111,000,000

[1] $2,169 million of residential first mortgages, $568 million of home equity loans and $111 million of commercial market loans do not have a specific allowance.

[2] Recorded investment in a loan includes net deferred loan fees and costs, unamortized premium or discount and direct write-downs and includes accrued interest only on credit card loans.

[3] Prior to 2008, the Company’s financial accounting systems did not separately track impaired smaller-balance, homogeneous consumer loans whose terms were modified due to the borrowers’ financial difficulties and where it was determined that a concession was granted to the borrower. Smaller-balance consumer loans modified since January 1, 2008 amounted to $23.4 billion at December 31, 2013. However, information derived from Citi’s risk management systems indicates that the amounts of outstanding modified loans, including those modified prior to 2008, approximated $24.0 billion at December 31, 2013.

[4] Prior to 2008, the Company’s financial accounting systems did not separately track impaired smaller-balance, homogeneous consumer loans whose terms were modified due to the borrowers’ financial difficulties and where it was determined that a concession was granted to the borrower. Smaller-balance consumer loans modified since January 1, 2008 amounted to $21.9 billion at June 30, 2014. However, information derived from Citi’s risk management systems indicates that the amounts of outstanding modified loans, including those modified prior to 2008, approximated $22.5 billion at June 30, 2014.

[5] Included in the Allowance for loan losses.

[6] Average carrying value represents the average recorded investment ending balance for the last four quarters and does not include the related specific allowance.

[7] Average carrying value represents the average recorded investment ending balance for last four quarters and does not include related specific allowance.

[8] Cash interest receipts on smaller-balance homogeneous loans are generally recorded as revenue. The interest recognition policy for commercial market loans is identical to that for corporate loans, as described below.

[9] Includes amounts recognized on both an accrual and cash basis.

[10] $2,106 million of residential first mortgages, $564 million of home equity loans and $86 million of commercial market loans do not have a specific allowance.