CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Citigroup’s net income		$ 7,942	$ 2,536
Add: Citigroup’s other comprehensive income
Net change in unrealized gains and losses on debt securities, net of taxes	[1]	(1,785)	3,128
Net change in debt valuation adjustment (DVA), net of taxes	[2]	(42)	3,140
Net change in cash flow hedges, net of taxes	[1]	(556)	1,897
Benefit plans liability adjustment, net of taxes	[1]	714	(286)
Net change in foreign currency translation adjustment, net of taxes and hedges	[1]	(1,274)	(4,109)
Net change in excluded component of fair value hedges, net of taxes	[1]	(10)	27
Citigroup’s total other comprehensive income (loss)	[1]	(2,953)	3,797
Citigroup’s total comprehensive income		4,989	6,333
Add: Other comprehensive loss attributable to noncontrolling interests		(58)	(51)
Add: Net income (loss) attributable to noncontrolling interests		33	(6)
Total comprehensive income		$ 4,964	$ 6,276

[1] See Note 17 to the Consolidated Financial Statements.

[2] See Note 20 to the Consolidated Financial Statements.