SUBSIDIARY GUARANTEES - Summarized Income Statement (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Condensed Income Statements
Revenues, net of interest expense	$ 20,139	$ 19,436	$ 41,243	$ 40,883
Total operating expenses	13,353	13,570	27,548	26,859
Provision for credit losses	2,359	1,761	4,781	3,498
Income from continuing operations before income taxes	4,310	4,042	8,854	10,225
Provision (benefits) for income taxes	1,047	1,090	2,183	2,621
Citigroup’s net income	$ 3,217	$ 2,915	6,588	$ 7,521
Citigroup Inc. | Reportable legal entities
Condensed Income Statements
Revenues, net of interest expense			2,084
Total operating expenses			172
Provision for credit losses			0
Equity in undistributed income of subsidiaries			4,307
Income from continuing operations before income taxes			6,219
Provision (benefits) for income taxes			(369)
Citigroup’s net income			6,588
CGMHI | Reportable legal entities
Condensed Income Statements
Revenues, net of interest expense			5,789
Total operating expenses			6,153
Provision for credit losses			20
Equity in undistributed income of subsidiaries			0
Income from continuing operations before income taxes			(384)
Provision (benefits) for income taxes			91
Citigroup’s net income			$ (475)