v3.26.1
CHANGES IN ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (AOCI) - Schedule of Pre-Tax and After-Tax (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Change in accumulated other comprehensive income (loss), after-tax        
Balance, beginning of period     $ 213,822  
Balance, end of period $ 214,450 $ 214,130 214,450 $ 214,130
Citigroup's accumulated other comprehensive income (loss)        
Change in accumulated other comprehensive income (loss), pretax        
Balance, beginning of period, pretax (46,774) (51,933) (48,156) (54,439)
Other comprehensive income (loss), pretax 898 2,006 2,280 4,512
Balance, end of period, pretax (45,876) (49,927) (45,876) (49,927)
Change in accumulated other comprehensive income (loss), tax effect        
Balance, beginning of period, tax effect 6,159 6,211 6,259 6,587
Other comprehensive income (loss), tax effect 217 (70) 117 (446)
Balance, end of period, tax effect 6,376 6,141 6,376 6,141
Change in accumulated other comprehensive income (loss), after-tax        
Balance, beginning of period (40,615) (45,722) (41,897) (47,852)
Total other comprehensive income (1,087) 1,936 195 4,066
Change 1,115   2,397  
Balance, end of period (39,500) (43,786) (39,500) (43,786)
Net unrealized gains (losses) on debt securities        
Change in accumulated other comprehensive income (loss), pretax        
Other comprehensive income (loss), pretax 305 363 (845) 1,107
Change in accumulated other comprehensive income (loss), tax effect        
Other comprehensive income (loss), tax effect (71) (85) 260 (314)
Change in accumulated other comprehensive income (loss), after-tax        
Balance, beginning of period (2,059) (2,322) (1,240) (2,837)
Total other comprehensive income 234 278 (585) 793
Change 234   (585)  
Balance, end of period (1,825) (2,044) (1,825) (2,044)
Debt valuation adjustment (DVA)        
Change in accumulated other comprehensive income (loss), pretax        
Other comprehensive income (loss), pretax (1,403) (391) 429 609
Change in accumulated other comprehensive income (loss), tax effect        
Other comprehensive income (loss), tax effect 314 49 (113) (172)
Change in accumulated other comprehensive income (loss), after-tax        
Balance, beginning of period (738) (342) (2,143) (1,121)
Total other comprehensive income (1,089) (342) 316 437
Change (1,089)   316  
Balance, end of period (1,827) (684) (1,827) (684)
Excluded component of fair value hedges        
Change in accumulated other comprehensive income (loss), after-tax        
Balance, beginning of period (21) (45) (34) (52)
Total other comprehensive income   0   7
Change 4   17  
Balance, end of period (17) (45) (17) (45)
Benefit plans        
Change in accumulated other comprehensive income (loss), pretax        
Other comprehensive income (loss), pretax 400 (57) 496 (75)
Change in accumulated other comprehensive income (loss), tax effect        
Other comprehensive income (loss), tax effect (115) 20 (173) 12
Change in accumulated other comprehensive income (loss), after-tax        
Balance, beginning of period (5,466) (5,653) (5,504) (5,627)
Total other comprehensive income 285 (37) 323 (63)
Change 285   323  
Balance, end of period (5,181) (5,690) (5,181) (5,690)
Foreign currency translation adjustment (CTA)        
Change in accumulated other comprehensive income (loss), pretax        
Other comprehensive income (loss), pretax 1,966 2,003 2,873 2,767
Change in accumulated other comprehensive income (loss), tax effect        
Other comprehensive income (loss), tax effect 1 (37) (17) 48
Change in accumulated other comprehensive income (loss), after-tax        
Balance, beginning of period (32,127) (37,198) (33,016) (38,047)
Total other comprehensive income 1,967 1,966 2,856 2,815
Change 1,967   2,856  
Balance, end of period (30,160) (35,232) (30,160) (35,232)
Long-duration insurance contracts        
Change in accumulated other comprehensive income (loss), pretax        
Other comprehensive income (loss), pretax (23) 2 (15) 0
Change in accumulated other comprehensive income (loss), tax effect        
Other comprehensive income (loss), tax effect 8 (3) 5 (2)
Change in accumulated other comprehensive income (loss), after-tax        
Balance, beginning of period 35 51 30 52
Total other comprehensive income (15) (1) (10) (2)
Change (15)   (10)  
Balance, end of period 20 50 20 50
Cash flow hedges | Excluded component of fair value hedges        
Change in accumulated other comprehensive income (loss), pretax        
Other comprehensive income (loss), pretax (349) 88 (679) 96
Change in accumulated other comprehensive income (loss), tax effect        
Other comprehensive income (loss), tax effect 78 (16) 159 (17)
Change in accumulated other comprehensive income (loss), after-tax        
Total other comprehensive income (271) 72 (520) 79
Excluded component of fair value hedges | Excluded component of fair value hedges        
Change in accumulated other comprehensive income (loss), pretax        
Other comprehensive income (loss), pretax 2 (2) 21 8
Change in accumulated other comprehensive income (loss), tax effect        
Other comprehensive income (loss), tax effect 2 2 (4) (1)
Change in accumulated other comprehensive income (loss), after-tax        
Total other comprehensive income $ 4 $ 0 $ 17 $ 7