Represents the rate at which principal will not be repaid on securitized financial assets. This is used as a key input and assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, as of the date of the latest statement of financial position presented.

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The weighted average life of securitized assets. This is used as a key input and assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement, if any, as of the date of the latest statement of financial position presented.

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This element represents the high end of range of discount rate which is used to value residual cash flows generated by financial assets of the securitization or asset-backed financing arrangement. This is used as a key assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, at the time of securitization or asset-backed financing.

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This element represents the low end of range of discount rate which is used to value residual cash flows generated by financial assets of the securitization or asset-backed financing arrangement. This is used as a key assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, at the time of securitization or asset-backed financing.

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This element represents the high end of range of constant prepayments of principal on financial assets. This is used as a key assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, at the time of securitization or asset-backed financing.

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The payment of maturing notes related to securitizations.

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This element represents expected the amount of principal that will not be repaid on securitized financial assets. This is used as a key input and assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, as of the date of the latest statement of financial position presented.

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The discount rate which is used to value residual cash flows generated by financial assets of the securitization or asset-backed financing arrangement. This is used as a key assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, as of the date of the latest statement of financial position presented.

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The rate at which principal will not be repaid on securitized financial assets. This is used as a key input and assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, as of the date of the latest statement of financial position presented.

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The discount rate which is used to value residual cash flows generated by financial assets of the securitization or asset-backed financing arrangement. This is used as a key assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, at the time of securitization or asset-backed financing.

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The rate at which principal will not be repaid on securitized financial assets. This is used as a key input and assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, at the time of securitization or asset-backed financing.

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Estimated speed of prepayments of principal on financial assets. This is used as a key assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, at the time of securitization or asset-backed financing.

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This amount represents total cash flows received from retained interests by the transferor other than servicing fees. Other cash flows include, for example, all cash flows from interest-only strips and cash above the minimum required level in cash collateral accounts.

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The amount of proceeds from new securitizations or asset-backed financing arrangements during this reporting period for this class of securitization or asset-backed financing arrangement.

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The amount of servicing fees from the securitization or asset-backed financing arrangement SPE.

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A gain or loss realized on a transfer, accounted for as a sale, of all or a portion of financial assets in which the transferor surrenders control and receives consideration other than a beneficial interest in the assets transferred. Reflects the amount of sales proceeds in excess of, or deficient from, the sum of the carrying amounts of transferred financial assets plus transaction costs.

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The carrying amount (fair value) as of the balance sheet date of interests in financial instruments (typically securitized receivables) that continue to be held (which are generally not involved in the collection of principal) following transfer of significant portions of such financial instruments to other parties. Such interests could be ancillary cash flows and interest-only strips.

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The hypothetical financial impact of a 10 percent adverse change of the discount rate on the fair value of interests that continue to be held by the transferor, servicing assets, or servicing liabilities as of the balance sheet date.

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The hypothetical financial impact of a 10 percent adverse change of the expected credit losses on the fair value of interests that continue to be held by the transferor, servicing assets, or servicing liabilities as of the balance sheet date.

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The hypothetical financial impact of a 10 percent adverse change of prepayment speed on the fair value of interests that continue to be held by the transferor, servicing assets, or servicing liabilities as of the balance sheet date.

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The hypothetical financial impact of a 20 percent adverse change of the discount rate on the fair value of interests that continue to be held by the transferor, servicing assets, or servicing liabilities as of the balance sheet date.

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SECURITIZATIONS AND VARIABLE INTEREST ENTITIES (Details 6) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Citicorp \| U.S. government-sponsored agency guaranteed
Classification of Securitizations
Proceeds from new securitizations	11,100,000,000		25,800,000,000
Contractual servicing fees received	100,000,000		300,000,000
Gains (losses) recognized on the securitization	(6,200,000)		(7,000,000)
Discount rate, high end of range (as a percent)	23.70%		28.30%
Discount rate, low end of range (as a percent)	0.60%		0.60%
Constant prepayment rate, high end of range (as a percent)	22.60%		22.60%
Constant prepayment rate, low end of range (as a percent)	3.60%		2.20%
Discount rate assumption for fair value of assets or liabilities that relate to transferor's continuing involvement (as a percent)	10.40%		10.60%
Carrying value of retained interests, impact of 10% adverse change in discount rate	(104,000,000)		(104,000,000)
Assumption for Fair Value of Interests Continued to be Held by Transferor Servicing Assets or Liabilities Weighted-average Expected Credit Losses	7.30%		5.70%
Carrying value of retained interests, impact of 20% adverse change in discount rate	(206,000,000)		(206,000,000)
Carrying value of retained interests, impact of 10% adverse change in constant prepayment rate	(94,000,000)		(94,000,000)
Carrying value of retained interests, impact of 20% adverse change in constant prepayment rate	(185,000,000)		(185,000,000)
Carrying value of retained interests, impact of 10% adverse change in anticipated net credit losses	(9,000,000)		(9,000,000)
Carrying value of retained interests, impact of 20% adverse change in anticipated net credit losses	(18,000,000)		(18,000,000)
Carrying value of retained interests	3,146,000,000		3,146,000,000
Citi Holdings \| U.S. government-sponsored agency guaranteed
Classification of Securitizations
Proceeds from new securitizations	300,000,000		600,000,000
Contractual servicing fees received	100,000,000		300,000,000
Discount rate (as a percent)			13.30%
Constant prepayment rate (as a percent)			14.00%
Discount rate assumption for fair value of assets or liabilities that relate to transferor's continuing involvement (as a percent)			13.30%
Carrying value of retained interests, impact of 10% adverse change in discount rate	(83,000,000)		(83,000,000)
Assumption for Fair Value of Interests Continued to be Held by Transferor Servicing Assets or Liabilities Weighted-average Expected Credit Losses			14.00%
Carrying value of retained interests, impact of 20% adverse change in discount rate	(160,000,000)		(160,000,000)
Carrying value of retained interests, impact of 10% adverse change in constant prepayment rate	(103,000,000)		(103,000,000)
Carrying value of retained interests, impact of 20% adverse change in constant prepayment rate	(199,000,000)		(199,000,000)
Carrying value of retained interests, impact of 10% adverse change in anticipated net credit losses	(34,000,000)		(34,000,000)
Carrying value of retained interests, impact of 20% adverse change in anticipated net credit losses	(68,000,000)		(68,000,000)
Carrying value of retained interests	1,979,000,000		1,979,000,000
Weighted average life assumption for fair value of assets or liabilities that relate to transferor's continuing involvement (in years)			6.2
Citicorp \| Non-agency-sponsored mortgages
Classification of Securitizations
Proceeds from new securitizations			100,000,000
Gains (losses) recognized on the securitization	(200,000)		(700,000)
Citi Holdings \| Non-agency-sponsored mortgages
Classification of Securitizations
Contractual servicing fees received			100,000,000
Non-agency-sponsored mortgages
Classification of Securitizations
Weighted average life, low end of range (in years)			0.8
Citicorp \| Senior Interests
Classification of Securitizations
Discount rate, high end of range (as a percent)			10.00%
Discount rate, low end of range (as a percent)			2.40%
Discount rate (as a percent)	10.00%
Constant prepayment rate, high end of range (as a percent)			2.20%
Constant prepayment rate, low end of range (as a percent)			1.00%
Constant prepayment rate (as a percent)	1.00%
Anticipated net credit losses, high end of range (as a percent)			72.00%
Anticipated net credit losses, low end of range (as a percent)			35.00%
Anticipated net credit losses (as a percent)	72.00%
Discount rate assumption for fair value of assets or liabilities that relate to transferor's continuing involvement (as a percent)	10.00%		4.50%
Carrying value of retained interests, impact of 10% adverse change in discount rate	(10,000,000)		(10,000,000)
Assumption for Fair Value of Interests Continued to be Held by Transferor Servicing Assets or Liabilities Weighted-average Expected Credit Losses	1.00%		1.90%
Carrying value of retained interests, impact of 20% adverse change in discount rate	(20,000,000)		(20,000,000)
Carrying value of retained interests, impact of 10% adverse change in constant prepayment rate	(8,000,000)		(8,000,000)
Carrying value of retained interests, impact of 20% adverse change in constant prepayment rate	(16,000,000)		(16,000,000)
Carrying value of retained interests, impact of 10% adverse change in anticipated net credit losses	(18,000,000)		(18,000,000)
Expected credit losses assumption for fair value of assets or liabilities that relate to transferor's continuing involvement (as a percent)	72.00%		45.30%
Carrying value of retained interests, impact of 20% adverse change in anticipated net credit losses	(29,000,000)		(29,000,000)
Carrying value of retained interests	276,000,000		276,000,000
Citi Holdings \| Senior Interests
Classification of Securitizations
Discount rate, high end of range (as a percent)			15.80%
Discount rate, low end of range (as a percent)			4.70%
Constant prepayment rate, high end of range (as a percent)			100.00%
Constant prepayment rate, low end of range (as a percent)			8.00%
Anticipated net credit losses, high end of range (as a percent)			60.00%
Anticipated net credit losses, low end of range (as a percent)			0.30%
Discount rate assumption for fair value of assets or liabilities that relate to transferor's continuing involvement (as a percent)			6.80%
Carrying value of retained interests, impact of 10% adverse change in discount rate	(7,000,000)		(7,000,000)
Assumption for Fair Value of Interests Continued to be Held by Transferor Servicing Assets or Liabilities Weighted-average Expected Credit Losses			18.60%
Carrying value of retained interests, impact of 20% adverse change in discount rate	(13,000,000)		(13,000,000)
Carrying value of retained interests, impact of 10% adverse change in constant prepayment rate	(24,000,000)		(24,000,000)
Carrying value of retained interests, impact of 20% adverse change in constant prepayment rate	(47,000,000)		(47,000,000)
Carrying value of retained interests, impact of 10% adverse change in anticipated net credit losses	(16,000,000)		(16,000,000)
Carrying value of retained interests, impact of 20% adverse change in anticipated net credit losses	(29,000,000)		(29,000,000)
Carrying value of retained interests	316,000,000		316,000,000
Weighted average life, high end of range (in years)			5.6
Weighted average life, low end of range (in years)			4.3
Expected credit losses assumption for fair value of assets or liabilities that relate to transferor's continuing involvement (as a percent)			3.50%
Citicorp \| Subordinated Interests
Classification of Securitizations
Discount rate (as a percent)			8.40%
Constant prepayment rate (as a percent)			22.10%
Anticipated net credit losses (as a percent)			11.40%
Discount rate assumption for fair value of assets or liabilities that relate to transferor's continuing involvement (as a percent)			8.40%
Carrying value of retained interests, impact of 10% adverse change in discount rate	(12,000,000)		(12,000,000)
Assumption for Fair Value of Interests Continued to be Held by Transferor Servicing Assets or Liabilities Weighted-average Expected Credit Losses			22.10%
Carrying value of retained interests, impact of 20% adverse change in discount rate	(23,000,000)		(23,000,000)
Carrying value of retained interests, impact of 10% adverse change in constant prepayment rate	(4,000,000)		(4,000,000)
Carrying value of retained interests, impact of 20% adverse change in constant prepayment rate	(9,000,000)		(9,000,000)
Carrying value of retained interests, impact of 10% adverse change in anticipated net credit losses	(21,000,000)		(21,000,000)
Expected credit losses assumption for fair value of assets or liabilities that relate to transferor's continuing involvement (as a percent)			11.40%
Carrying value of retained interests, impact of 20% adverse change in anticipated net credit losses	(38,000,000)		(38,000,000)
Carrying value of retained interests	275,000,000		275,000,000
Citi Holdings \| Subordinated Interests
Classification of Securitizations
Discount rate, high end of range (as a percent)			10.00%
Discount rate, low end of range (as a percent)			0.10%
Constant prepayment rate, high end of range (as a percent)			3.00%
Constant prepayment rate, low end of range (as a percent)			2.00%
Anticipated net credit losses, high end of range (as a percent)			95.00%
Anticipated net credit losses, low end of range (as a percent)			40.00%
Discount rate assumption for fair value of assets or liabilities that relate to transferor's continuing involvement (as a percent)			3.40%
Carrying value of retained interests, impact of 10% adverse change in discount rate	(3,000,000)		(3,000,000)
Assumption for Fair Value of Interests Continued to be Held by Transferor Servicing Assets or Liabilities Weighted-average Expected Credit Losses			0.80%
Carrying value of retained interests, impact of 20% adverse change in discount rate	(3,000,000)		(3,000,000)
Carrying value of retained interests, impact of 10% adverse change in anticipated net credit losses	(3,000,000)		(3,000,000)
Carrying value of retained interests, impact of 20% adverse change in anticipated net credit losses	(4,000,000)		(4,000,000)
Carrying value of retained interests	12,000,000		12,000,000
Weighted average life, high end of range (in years)			8.2
Weighted average life, low end of range (in years)			0.6
Expected credit losses assumption for fair value of assets or liabilities that relate to transferor's continuing involvement (as a percent)			34.70%
Citicorp \| Mortgage-backed securities
Classification of Securitizations
Proceeds from new securitizations		12,000,000,000		24,300,000,000
Contractual servicing fees received		100,000,000		300,000,000
Gains (losses) recognized on the securitization		(1,000,000)		3,000,000
Discount rate, high end of range (as a percent)	39.80%		39.80%
Discount rate, low end of range (as a percent)	0.90%		0.90%
Constant prepayment rate, high end of range (as a percent)	25.00%		25.00%
Constant prepayment rate, low end of range (as a percent)	3.00%		3.00%
Anticipated net credit losses, high end of range (as a percent)	75.00%		75.00%
Anticipated net credit losses, low end of range (as a percent)	40.00%		40.00%
Citi Holdings \| Mortgage-backed securities
Classification of Securitizations
Contractual servicing fees received		300,000,000		500,000,000
Cash flows received on retained interests and other net cash flows		100,000,000		100,000,000
Citicorp \| Collateralized debt obligations (CDOs)
Classification of Securitizations
Discount rate, high end of range (as a percent)			45.80%
Discount rate, low end of range (as a percent)			42.00%
Carrying value of retained interests, impact of 10% adverse change in discount rate	(2,000,000)		(2,000,000)
Carrying value of retained interests, impact of 20% adverse change in discount rate	(3,000,000)		(3,000,000)
Carrying value of retained interests	14,000,000		14,000,000
Citicorp \| Collateralized loan obligations (CLOs)
Classification of Securitizations
Discount rate, high end of range (as a percent)			5.00%
Discount rate, low end of range (as a percent)			4.50%
Carrying value of retained interests, impact of 10% adverse change in discount rate	(1,000,000)		(1,000,000)
Carrying value of retained interests, impact of 20% adverse change in discount rate	(1,000,000)		(1,000,000)
Carrying value of retained interests	251,000,000		251,000,000
Citi Holdings \| Asset-based financing
Classification of Securitizations
Cash flows received on retained interests and other net cash flows	500,000,000	400,000,000	900,000,000	900,000,000
Carrying value of retained interests, impact of 20% adverse change in discount rate	(35,000,000)		(35,000,000)
Carrying value of retained interests	4,387,000,000		4,387,000,000
Citicorp \| Credit card securitizations
Classification of Securitizations
Pay down of maturing notes	(10,800,000,000)	(6,900,000,000)	(10,800,000,000)	(17,400,000,000)
Citi Holdings \| Credit card securitizations
Classification of Securitizations
Proceeds from new securitizations	3,000,000,000	2,100,000,000	3,900,000,000	3,800,000,000
Pay down of maturing notes	(4,800,000,000)	(4,000,000,000)	(7,200,000,000)	(13,800,000,000)
Municipal securities tender option bond trusts (TOBs)
Classification of Securitizations
Proceeds from new securitizations			100,000,000