CONDENSED CONSOLIDATING FINANCIAL STATEMENTS OF INCOME (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Condensed Consolidating Statements of Income:
Interest revenue	$ 17,537	$ 18,155
Interest expense	5,590	6,053
Net interest revenue	11,947	12,102
Commissions and fees	3,138	3,368
Principal transactions	1,931	3,167
Other income	2,390	1,089
Total non-interest revenues	7,459	7,624
Total revenues, net of interest expense	19,406	19,726
Provisions for credit losses and for benefits and claims	3,019	3,184
Compensation and benefits	6,385	6,409
Other expense	5,934	5,917
Total operating expenses	12,319	12,326
Income (loss) before taxes and equity in undistributed income of subsidiaries	4,068	4,216
Provision (benefit) for income taxes	1,006	1,185
Income from continuing operations	3,062	3,031
Income (loss) from discontinued operations, net of taxes	(5)	40
Net income before attribution of noncontrolling interests	3,057	3,071
Net income (loss) attributable to noncontrolling interests	126	72
Citigroup's net income	2,931	2,999
Citigroup Parent Company
Condensed Consolidating Statements of Income:
Dividends from subsidiaries	1,500	525
Interest revenue	66	52
Interest revenue-intercompany	908	944
Interest expense	1,940	2,048
Interest expense-intercompany	(115)	(187)
Net interest revenue	(851)	(865)
Principal transactions	67	43
Principal transactions-intercompany	10	1
Other income	1,265	15
Other income-intercompany	(1,467)	(175)
Total non-interest revenues	(125)	(116)
Total revenues, net of interest expense	524	(456)
Compensation and benefits	60	44
Compensation and benefits-intercompany	2	2
Other expense	407	310
Other expense-intercompany	127	109
Total operating expenses	596	465
Income (loss) before taxes and equity in undistributed income of subsidiaries	(72)	(921)
Provision (benefit) for income taxes	91	(640)
Equity in undistributed income of subsidiaries	3,094	3,280
Income from continuing operations	2,931	2,999
Net income before attribution of noncontrolling interests	2,931	2,999
Citigroup's net income	2,931	2,999
Citigroup Global Markets Holdings Inc. (CGMHI)
Condensed Consolidating Statements of Income:
Interest revenue	1,253	1,468
Interest revenue-intercompany	239	542
Interest expense	483	551
Interest expense-intercompany	631	811
Net interest revenue	378	648
Commissions and fees	1,090	1,148
Commissions and fees-intercompany	30	(1)
Principal transactions	(60)	(171)
Principal transactions-intercompany	781	1,223
Other income	171	315
Other income-intercompany	(322)	(75)
Total non-interest revenues	1,690	2,439
Total revenues, net of interest expense	2,068	3,087
Provisions for credit losses and for benefits and claims	5	10
Compensation and benefits	1,403	1,459
Compensation and benefits-intercompany	55	57
Other expense	590	680
Other expense-intercompany	181	79
Total operating expenses	2,229	2,275
Income (loss) before taxes and equity in undistributed income of subsidiaries	(166)	802
Provision (benefit) for income taxes	(154)	372
Income from continuing operations	(12)	430
Net income before attribution of noncontrolling interests	(12)	430
Net income (loss) attributable to noncontrolling interests	9	11
Citigroup's net income	(21)	419
Citigroup Funding Inc. (CFI)
Condensed Consolidating Statements of Income:
Interest revenue	7
Interest revenue-intercompany	342	604
Interest expense	382	534
Interest expense-intercompany	(108)	194
Net interest revenue	75	(124)
Principal transactions	(1,008)	234
Principal transactions-intercompany	277	(229)
Other income	30	55
Other income-intercompany	(123)	(165)
Total non-interest revenues	(824)	(105)
Total revenues, net of interest expense	(749)	(229)
Other expense		1
Other expense-intercompany	1	1
Total operating expenses	1	2
Income (loss) before taxes and equity in undistributed income of subsidiaries	(750)	(231)
Provision (benefit) for income taxes	(281)	(129)
Income from continuing operations	(469)	(102)
Net income before attribution of noncontrolling interests	(469)	(102)
Citigroup's net income	(469)	(102)
CitiFinancial Credit Company (CCC)
Condensed Consolidating Statements of Income:
Interest revenue	846	1,051
Interest revenue-intercompany	25	26
Interest expense	26	29
Interest expense-intercompany	277	396
Net interest revenue	568	652
Commissions and fees	2	2
Commissions and fees-intercompany	(2)	28
Other income	(94)	111
Total non-interest revenues	(94)	141
Total revenues, net of interest expense	474	793
Provisions for credit losses and for benefits and claims	468	397
Compensation and benefits	94	107
Compensation and benefits-intercompany	27	30
Other expense	92	200
Other expense-intercompany	23	91
Total operating expenses	236	428
Income (loss) before taxes and equity in undistributed income of subsidiaries	(230)	(32)
Provision (benefit) for income taxes	(111)	(28)
Income from continuing operations	(119)	(4)
Net income before attribution of noncontrolling interests	(119)	(4)
Citigroup's net income	(119)	(4)
Associates
Condensed Consolidating Statements of Income:
Interest revenue	985	1,225
Interest revenue-intercompany	95	97
Interest expense	69	76
Interest expense-intercompany	250	324
Net interest revenue	761	922
Commissions and fees	22	23
Commissions and fees-intercompany	4	32
Principal transactions	4	1
Other income	(59)	139
Other income-intercompany	(27)	10
Total non-interest revenues	(56)	205
Total revenues, net of interest expense	705	1,127
Provisions for credit losses and for benefits and claims	506	456
Compensation and benefits	131	148
Compensation and benefits-intercompany	27	30
Other expense	129	238
Other expense-intercompany	27	100
Total operating expenses	314	516
Income (loss) before taxes and equity in undistributed income of subsidiaries	(115)	155
Provision (benefit) for income taxes	(70)	40
Income from continuing operations	(45)	115
Net income before attribution of noncontrolling interests	(45)	115
Citigroup's net income	(45)	115
Other Citigroup Subsidiaries, eliminations and income from discontinued operations
Condensed Consolidating Statements of Income:
Interest revenue	15,226	15,410
Interest revenue-intercompany	(1,584)	(2,187)
Interest expense	2,716	2,844
Interest expense-intercompany	(658)	(1,142)
Net interest revenue	11,584	11,521
Commissions and fees	2,026	2,197
Commissions and fees-intercompany	(34)	(31)
Principal transactions	2,928	3,060
Principal transactions-intercompany	(1,068)	(995)
Other income	983	565
Other income-intercompany	1,939	405
Total non-interest revenues	6,774	5,201
Total revenues, net of interest expense	18,358	16,722
Provisions for credit losses and for benefits and claims	2,508	2,718
Compensation and benefits	4,791	4,758
Compensation and benefits-intercompany	(84)	(89)
Other expense	4,808	4,688
Other expense-intercompany	(336)	(289)
Total operating expenses	9,179	9,068
Income (loss) before taxes and equity in undistributed income of subsidiaries	6,671	4,936
Provision (benefit) for income taxes	1,420	1,542
Income from continuing operations	5,251	3,394
Income (loss) from discontinued operations, net of taxes	(5)	40
Net income before attribution of noncontrolling interests	5,246	3,434
Net income (loss) attributable to noncontrolling interests	117	61
Citigroup's net income	5,129	3,373
Consolidating adjustments
Condensed Consolidating Statements of Income:
Dividends from subsidiaries	(1,500)	(525)
Interest revenue	(846)	(1,051)
Interest revenue-intercompany	(25)	(26)
Interest expense	(26)	(29)
Interest expense-intercompany	(277)	(396)
Net interest revenue	(568)	(652)
Commissions and fees	(2)	(2)
Commissions and fees-intercompany	2	(28)
Other income	94	(111)
Total non-interest revenues	94	(141)
Total revenues, net of interest expense	(1,974)	(1,318)
Provisions for credit losses and for benefits and claims	(468)	(397)
Compensation and benefits	(94)	(107)
Compensation and benefits-intercompany	(27)	(30)
Other expense	(92)	(200)
Other expense-intercompany	(23)	(91)
Total operating expenses	(236)	(428)
Income (loss) before taxes and equity in undistributed income of subsidiaries	(1,270)	(493)
Provision (benefit) for income taxes	111	28
Equity in undistributed income of subsidiaries	(3,094)	(3,280)
Income from continuing operations	(4,475)	(3,801)
Net income before attribution of noncontrolling interests	(4,475)	(3,801)
Citigroup's net income	$ (4,475)	$ (3,801)