CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY (UNAUDITED) - 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	Retained earnings Cumulative Effect, Period of Adoption, Adjustment	[1]	Retained earnings Cumulative Effect, Period of Adoption, Adjusted Balance	Treasury stock, at cost		Citigroup's accumulated other comprehensive income (loss)	Noncontrolling interests
Balance, beginning of period at Dec. 31, 2018				$ 18,460		$ 107,953	$ 151,347	$ 151		$ 151,498	$ (44,370)		$ (37,170)	$ 854
Increase (Decrease) in Stockholders' Equity
Issuance of new preferred stock				0
Redemption of preferred stock				(480)
Employee benefit plans						(270)					573	[2]
Preferred stock issuance costs						0
Common dividends	[3]						(2,116)
Preferred dividends		$ (558)					(558)
Other						5	(12)							(9)
Treasury stock acquired	[4]										(7,630)
Citigroup's total other comprehensive income (loss)													1,967	7
Transactions between Citigroup and the noncontrolling-interest shareholders														(99)
Net income before attribution of noncontrolling interests		9,544					9,509							35
Distributions paid to noncontrolling-interest shareholders														(37)
Net change in noncontrolling interests														(103)
Balance, end of period at Jun. 30, 2019		198,110	$ 197,359	17,980	$ 179,379	107,688	158,321				(51,427)		(35,203)	751
Balance, beginning of period at Mar. 31, 2019				17,980		107,582	154,859	0		154,859	(47,861)		(36,308)	763
Increase (Decrease) in Stockholders' Equity
Issuance of new preferred stock				0
Redemption of preferred stock				0
Employee benefit plans						112					9	[2]
Preferred stock issuance costs						0
Common dividends	[3]						(1,041)
Preferred dividends		(296)					(296)
Other						(6)	0							(9)
Treasury stock acquired	[4]										(3,575)
Citigroup's total other comprehensive income (loss)													1,105	20
Transactions between Citigroup and the noncontrolling-interest shareholders														0
Net income before attribution of noncontrolling interests		4,809					4,799							10
Distributions paid to noncontrolling-interest shareholders														(33)
Net change in noncontrolling interests														(12)
Balance, end of period at Jun. 30, 2019		198,110	197,359	17,980	179,379	107,688	158,321				(51,427)		(35,203)	751
Balance, beginning of period at Dec. 31, 2019		193,946		17,980		107,871	165,369	(3,076)		162,293	(61,660)		(36,318)	704
Increase (Decrease) in Stockholders' Equity
Issuance of new preferred stock				1,500
Redemption of preferred stock				(1,500)
Employee benefit plans						(174)					442	[2]
Preferred stock issuance costs						2
Common dividends	[3]						(2,152)
Preferred dividends		(544)					(544)
Other						0	(4)							0
Treasury stock acquired	[4]										(2,925)
Citigroup's total other comprehensive income (loss)													2,973	(12)
Transactions between Citigroup and the noncontrolling-interest shareholders														(6)
Net income before attribution of noncontrolling interests		3,832					3,838							(6)
Distributions paid to noncontrolling-interest shareholders														0
Net change in noncontrolling interests														(24)
Balance, end of period at Jun. 30, 2020		192,302	191,622	17,980	173,642	107,699	163,431				(64,143)		(33,345)	680
Balance, beginning of period at Mar. 31, 2020				17,980		107,581	163,438	$ 0		$ 163,438	(64,147)		(32,521)	651
Increase (Decrease) in Stockholders' Equity
Issuance of new preferred stock				0
Redemption of preferred stock				0
Employee benefit plans						118					4	[2]
Preferred stock issuance costs						0
Common dividends	[3]						(1,071)
Preferred dividends		(253)					(253)
Other						0	1							(10)
Treasury stock acquired	[4]										0
Citigroup's total other comprehensive income (loss)													(824)	39
Transactions between Citigroup and the noncontrolling-interest shareholders														0
Net income before attribution of noncontrolling interests		1,316					1,316							0
Distributions paid to noncontrolling-interest shareholders														0
Net change in noncontrolling interests														29
Balance, end of period at Jun. 30, 2020		$ 192,302	$ 191,622	$ 17,980	$ 173,642	$ 107,699	$ 163,431				$ (64,143)		$ (33,345)	$ 680

[1] See Note 1 to the Consolidated Financial Statements for additional details.

[2] Includes treasury stock related to (i) certain 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 programs where shares are withheld to satisfy tax requirements.

[3] Common dividends declared were $0.51 per share in the first and second quarters of 2020. Common dividends declared were $0.45 per share in the first and second quarters of 2019.

[4] Primarily consists of open market purchases under Citi’s Board of Directors-approved common stock repurchase program.