SUBSIDIARY GUARANTEES - Summarized Income Statement (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Condensed Income Statements
Revenues, net of interest expense	$ 19,436	$ 19,638	$ 40,883	$ 38,824
Operating expense	13,570	12,393	26,859	25,558
Provision for credit losses	1,761	1,384	3,498	1,644
Income from continuing operations before income taxes	4,042	5,971	10,225	11,237
Provision (benefits) for income taxes	1,090	1,182	2,621	2,123
Citigroup’s net income	$ 2,915	$ 4,547	7,521	$ 8,853
Citigroup Inc. | Reportable legal entities
Condensed Income Statements
Revenues, net of interest expense			6,584
Operating expense			99
Provision for credit losses			0
Equity in undistributed income of subsidiaries			581
Income from continuing operations before income taxes			7,066
Provision (benefits) for income taxes			(455)
Citigroup’s net income			7,521
CGMHI | Reportable legal entities
Condensed Income Statements
Revenues, net of interest expense			5,960
Operating expense			5,911
Provision for credit losses			23
Equity in undistributed income of subsidiaries			0
Income from continuing operations before income taxes			26
Provision (benefits) for income taxes			54
Citigroup’s net income			$ (28)