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, 2011				$ 312		$ 105,833	$ 90,520	$ (1,071)	$ (17,788)	$ 1,767
Increase (Decrease) in Stockholders' Equity
Adjustment to opening balance, net of taxes	[1]						(107)
Adjusted balance, beginning of year							90,413
Citigroup's net income		2,931					2,931
Employee benefit plans						(19)
Common dividends	[2]						(30)
Preferred dividends		(4)					(4)
Issuance of shares pursuant to employee benefit plans								192
Treasury stock acquired	[3]							(4)
Transactions between Citigroup and the noncontrolling-interest shareholders										(53)
Net income attributable to noncontrolling interests		126								(126)
Dividends paid to noncontrolling-interest shareholders										(4)
Other						2				3
Net change in Accumulated other comprehensive income (loss)		1,053							1,053
Total other comprehensive income (loss) attributable to noncontrolling interests		64								64
Net change in noncontrolling interests										136
Balance, end of period at Mar. 31, 2012		183,723	181,820	312	181,508	105,816	93,310	(883)	(16,735)	1,903
Balance, beginning of year at Dec. 31, 2012		190,997		2,562		106,421	97,809	(847)	(16,896)	1,948
Increase (Decrease) in Stockholders' Equity
Adjusted balance, beginning of year							97,809
Citigroup's net income		3,808					3,808
Employee benefit plans						286
Common dividends	[2]						(33)
Preferred dividends		(4)					(4)
Issuance of shares pursuant to employee benefit plans								(144)
Issuance of preferred stock				575
Transactions between noncontrolling-interest shareholders and the related consolidated subsidiary										(2)
Transactions between Citigroup and the noncontrolling-interest shareholders										16
Net income attributable to noncontrolling interests		90								(90)
Dividends paid to noncontrolling-interest shareholders										(4)
Other						(15)				(17)
Net change in Accumulated other comprehensive income (loss)		(163)							(163)
Total other comprehensive income (loss) attributable to noncontrolling interests		(51)								(51)
Net change in noncontrolling interests										32
Balance, end of period at Mar. 31, 2013		$ 195,339	$ 193,359	$ 3,137	$ 190,222	$ 106,692	$ 101,580	$ (991)	$ (17,059)	$ 1,980

[1] The adjustment to the opening balance for Retained earnings in the first quarter of 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.

[2] Common dividends declared were $0.01 per share in the first quarter of 2013 and 2012.

[3] Consists of shares added to treasury stock related to (i) activity on employee stock option program exercises where the employee delivers existing shares to cover the option exercise, or (ii) under Citi's employee restricted or deferred stock program where shares are withheld to satisfy tax requirements.