CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income before attribution of noncontrolling interests		$ 4,296	$ 2,900	$ 13,972	$ 7,120
Add: Citigroup’s other comprehensive income (loss)
Net change in unrealized gains and losses on investment securities, net of taxes		511	(207)	167	1,227
Net change in cash flow hedges, net of taxes		189	28	367	266
Benefit plans liability adjustment, net of taxes	[1]	(360)	71	128	(106)
Net change in foreign currency translation adjustment, net of taxes and hedges		(2,493)	(1,721)	(4,703)	(2,230)
Citigroup’s total other comprehensive income (loss)		(2,153)	(1,829)	(4,041)	(843)
Total comprehensive income before attribution of noncontrolling interests		2,143	1,071	9,931	6,277
Less: Net income attributable to noncontrolling interests		5	59	65	154
Citigroup’s comprehensive income		$ 2,138	$ 1,012	$ 9,866	$ 6,123

[1] Reflects adjustments based on the actuarial valuations of the Company’s significant pension and postretirement plans, including changes in the mortality assumptions at September 30, 2015, and amortization of amounts previously recognized in Accumulated other comprehensive income (loss). See Note 8 to the Consolidated Financial Statements.