v3.25.4
SECURITIZATIONS AND VARIABLE INTEREST ENTITIES - Credit Card Securitizations (Details) - USD ($)
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Ownership interests in principal amount of trust credit card receivables      
Sold to investors via trust-issued securities $ 5,400,000,000 $ 5,200,000,000  
Retained by Citigroup as trust-issued securities 2,500,000,000 3,700,000,000  
Retained by Citigroup via non-certificated interests 20,700,000,000 22,100,000,000  
Total ownership interests in principal amount of trust credit card receivables 28,600,000,000 31,000,000,000.0  
Credit card securitizations      
Securitized credit card receivables      
Gains (losses) recognized on the securitization 0    
Cash Flows Between Transferor and Transferee      
Proceeds from new securitizations 2,000,000,000.0 0 $ 1,500,000,000
Pay down of maturing notes $ (1,900,000,000) $ (1,700,000,000) $ (2,400,000,000)