CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY (USD $) In Millions, unless otherwise specified		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	Citigroup's accumulated other comprehensive income (loss)	Noncontrolling interest
Balance, beginning of year at Dec. 31, 2010		$ 165,789		$ 312		$ 101,316	$ 79,559	$ (1,442)	$ (16,277)	$ 2,321
Increase (Decrease) in Stockholders' Equity
Citigroup's net income (loss)		10,111					10,111
Employee benefit plans						526
ADIA Upper DECs Equity Units Purchase Contract						3,750
Common dividends	[1]						(52)
Preferred dividends		(17)					(17)
Issuance of shares pursuant to employee benefit plans								354
Treasury stock acquired	[2]							(1)
Initial origination of a noncontrolling interest										28
Transactions between Citigroup and the noncontrolling-interest shareholders										(351)
Net income attributable to noncontrolling interests		106								106
Dividends paid to noncontrolling-interest shareholders										(67)
Other						(1)	1			(5)
Net change in accumulated other comprehensive income (loss)									(767)
Total other comprehensive income (loss) attributable to noncontrolling interests		(62)								(62)
Net change in noncontrolling interests										(351)
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 (Prior Period Adjustment)							79,559
Balance, beginning of year at Dec. 31, 2010				312
Increase (Decrease) in Stockholders' Equity
Prior period adjustment (Prior Period Adjustment)	[3]						(107)
Balance, end of period (Prior Period Adjustment)							90,413
Balance, end of period at Dec. 31, 2011		179,573		312		105,833	90,520	(1,071)	(17,788)	1,767
Increase (Decrease) in Stockholders' Equity
Citigroup's net income (loss)		6,345					6,345
Employee benefit plans						391
Common dividends	[1]						(91)
Preferred dividends		(17)					(17)
Issuance of shares pursuant to employee benefit plans								224
Treasury stock acquired	[2]							(4)
Initial origination of a noncontrolling interest										88
Transactions between Citigroup and the noncontrolling-interest shareholders										(41)
Net income attributable to noncontrolling interests		191								191
Dividends paid to noncontrolling-interest shareholders										(32)
Other						8				(71)
Net change in accumulated other comprehensive income (loss)									2,222
Total other comprehensive income (loss) attributable to noncontrolling interests		59								59
Net change in noncontrolling interests										194
Balance, end of period at Sep. 30, 2012		$ 188,738	$ 186,777	$ 312	$ 186,465	$ 106,232	$ 96,650	$ (851)	$ (15,566)	$ 1,961

[1] Common dividends declared were as follows: $0.01 per share in the first, second and third quarters of 2012; $0.01 in the second and third quarters of 2011.

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

[3] The adjustment to the opening balance for Retained earnings in 2012 represents the cumulative effect of adopting ASU 2010-26, Financial Services-Insurance (Topic 944): Accounting for Costs Associated with Acquiring or Renewing Insurance Contracts. See Note 1 to the Consolidated Financial Statements.