CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY (USD $) In Millions		Total	Citigroup stockholders' equity	Preferred stock at aggregate liquidation value	Citigroup common stockholders' equity	Common stock and additional paid-in capital	Retained earnings	Treasury stock, at cost	Accumulated other comprehensive income (loss)	Noncontrolling interest	Comprehensive income (loss)
Balance, beginning of year at Dec. 31, 2009				$ 312					$ (18,937)
Increase (Decrease) in Stockholders' Equity
Net change in cash flow hedges, net of taxes									223
Accumulated other comprehensive income-net change in foreign currency translation adjustment, net of tax									(279)
Pension liability adjustment, net of taxes									(48)
Net change in Accumulated other comprehensive income (loss) before attribution of noncontrolling interest									1,078
Balance, end of period at Mar. 31, 2010
Balance, beginning of year at Dec. 31, 2009				312		98,428	68,957	(4,543)	(18,937)	2,273
Balance as Previously Reported at Dec. 31, 2009							77,440
Increase (Decrease) in Stockholders' Equity
Adjustment to opening balance, net of taxes	[1]						(8,483)
Citigroup's net income		9,412					9,293				9,412
Employee benefit plans						(834)
Conversion of ADIA Upper Decs Equity Units Purchase Contract to common stock						3,750
Common dividends	[2]						10
Issuance of shares pursuant to employee benefit plans								3,007
Treasury stock acquired	[3]							(5)
Accumulated other comprehensive income-net change in unrealized gains and losses on investment securities, net of tax									3,350	6
Net change in cash flow hedges, net of taxes									(123)
Accumulated other comprehensive income-net change in foreign currency translation adjustment, net of tax									440	(20)
Pension liability adjustment, net of taxes	[4]								(39)
Initial origination of a noncontrolling interest										287
Transactions between Citigroup and the noncontrolling-interest shareholders										(308)
Net income attributable to noncontrolling-interest shareholders		(119)								119
Dividends paid to noncontrolling-interest shareholders										(99)
Other						(154)		1		12
Net change in Accumulated other comprehensive income (loss) before attribution of noncontrolling interest									3,628		3,614
Net change in noncontrolling interests										(3)
Total comprehensive income before attribution of noncontrolling interest											13,026
Comprehensive income (loss) attributable to the noncontrolling interests											105
Comprehensive income attributable to Citigroup											12,921
Balance, end of period at Sep. 30, 2010		165,183	162,913	312	162,601	101,190	78,260	(1,540)	(15,309)	2,270
Balance, beginning of year at Jun. 30, 2010
Increase (Decrease) in Stockholders' Equity
Citigroup's net income		2,227
Net change in cash flow hedges, net of taxes									(121)
Accumulated other comprehensive income-net change in foreign currency translation adjustment, net of tax									2,755
Pension liability adjustment, net of taxes									(35)
Net income attributable to noncontrolling-interest shareholders		(59)
Net change in Accumulated other comprehensive income (loss) before attribution of noncontrolling interest									3,861
Balance, end of period at Sep. 30, 2010		165,183	162,913	312	162,601				(15,309)
Balance, beginning of year at Dec. 31, 2010				312					(16,277)
Increase (Decrease) in Stockholders' Equity
Net change in cash flow hedges, net of taxes									152
Accumulated other comprehensive income-net change in foreign currency translation adjustment, net of tax									1,364
Pension liability adjustment, net of taxes									37
Net change in Accumulated other comprehensive income (loss) before attribution of noncontrolling interest									2,293
Balance, end of period at Mar. 31, 2011
Balance, beginning of year at Dec. 31, 2010		165,789		312		101,316	79,559	(1,442)	(16,277)	2,321
Balance as Previously Reported at Dec. 31, 2010							79,559
Increase (Decrease) in Stockholders' Equity
Citigroup's net income		10,217					10,111				10,217
Employee benefit plans						526
Conversion of ADIA Upper Decs Equity Units Purchase Contract to common stock						3,750
Common dividends	[2]						(52)
Preferred dividends							(17)
Issuance of shares pursuant to employee benefit plans								354
Treasury stock acquired	[3]							(1)
Accumulated other comprehensive income-net change in unrealized gains and losses on investment securities, net of tax									2,297	(2)
Net change in cash flow hedges, net of taxes									(449)
Accumulated other comprehensive income-net change in foreign currency translation adjustment, net of tax									(2,795)	(60)
Pension liability adjustment, net of taxes	[4]								180
Initial origination of a noncontrolling interest										28
Transactions between Citigroup and the noncontrolling-interest shareholders										(351)
Net income attributable to noncontrolling-interest shareholders		(106)								106
Dividends paid to noncontrolling-interest shareholders										(67)
Other						(1)	1			(5)
Net change in Accumulated other comprehensive income (loss) before attribution of noncontrolling interest									(767)		(829)
Net change in noncontrolling interests										(351)
Total comprehensive income before attribution of noncontrolling interest											9,388
Comprehensive income (loss) attributable to the noncontrolling interests											44
Comprehensive income attributable to Citigroup											9,344
Balance, end of period at Sep. 30, 2011		179,342	177,372	312	177,060	105,591	89,602	(1,089)	(17,044)	1,970
Balance, beginning of year at Jun. 30, 2011
Increase (Decrease) in Stockholders' Equity
Citigroup's net income		3,743
Net change in cash flow hedges, net of taxes									(532)
Accumulated other comprehensive income-net change in foreign currency translation adjustment, net of tax									(4,935)
Pension liability adjustment, net of taxes									140
Net income attributable to noncontrolling-interest shareholders		28
Net change in Accumulated other comprehensive income (loss) before attribution of noncontrolling interest									(4,822)
Balance, end of period at Sep. 30, 2011		$ 179,342	$ 177,372	$ 312	$ 177,060				$ (17,044)

[1] The adjustment to the opening balance for Retained earnings in 2010 represents the cumulative effect of initially adopting ASC 810, Consolidation (SFAS 167).

[2] Common dividends in 2010 represent a reversal of dividends accrued on forfeitures of previously issued but unvested employee stock awards related to employees who have left Citigroup.

[3] All open market repurchases were transacted under an existing authorized share repurchase plan and relate to customer fails/errors.

[4] Reflects adjustments to the funded status of pension and postretirement plans, which is the difference between the fair value of the plan assets and the projected benefit obligation. See Note 8 to the Consolidated Financial Statements.