CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Citigroup's net income		$ 4,090	$ 3,501
Add: Citigroup's other comprehensive income
Net change in unrealized gains and losses on investment securities, net of taxes		220	2,034
Net change in debt valuation adjustment (DVA), net of taxes	[1]	(60)	193
Net change in cash flow hedges, net of taxes		(2)	317
Benefit plans liability adjustment, net of taxes		(12)	(465)
Net change in foreign currency translation adjustment, net of taxes and hedges		1,318	654
Citigroup’s total other comprehensive income		1,464	2,733
Add: Other comprehensive income attributable to noncontrolling interests		31	27
Citigroup’s total comprehensive income		5,554	6,234
Add: Net income attributable to noncontrolling interests		10	5
Total comprehensive income		$ 5,595	$ 6,266

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