v3.26.3
Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Loss) (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Accumulated other comprehensive income (loss) [Roll Forward]        
Balance, beginning of period     $ 32,894  
Other comprehensive income (loss), net of taxes $ (4,395) $ 991 (4,563) $ 1,873
Balance, end of period 28,995 31,609 28,995 31,609
Pre-tax components of other comprehensive income (loss) and the related income tax expense (benefit)        
Other comprehensive income (loss), before income taxes (5,574) 1,275 (5,882) 2,342
Income tax expense (benefit) (1,179) 284 (1,319) 469
Other comprehensive income (loss), net of taxes (4,395) 991 (4,563) 1,873
Accumulated Other Comprehensive Income (Loss) [Member]        
Accumulated other comprehensive income (loss) [Roll Forward]        
Balance, beginning of period (2,668) (4,085) (2,500) (4,967)
Other comprehensive income (loss) (OCI) before reclassifications, net of tax (4,406)   (4,950)  
Amounts reclassified from accumulated other comprehensive income (loss), net of tax 11   387  
Other comprehensive income (loss), net of taxes (4,395) 991 (4,563) 1,873
Balance, end of period (7,063) (3,094) (7,063) (3,094)
Pre-tax components of other comprehensive income (loss) and the related income tax expense (benefit)        
Other comprehensive income (loss), before income taxes (5,574) 1,275 (5,882) 2,342
Income tax expense (benefit) (1,179) 284 (1,319) 469
Other comprehensive income (loss), net of taxes (4,395) 991 (4,563) 1,873
Changes in Net Unrealized Gains (Losses) on Investment Securities Having No Credit Losses Recognized in the Consolidated Statement of Income [Member]        
Accumulated other comprehensive income (loss) [Roll Forward]        
Balance, beginning of period (2,145)   (1,664)  
Other comprehensive income (loss) (OCI) before reclassifications, net of tax (4,405)   (4,913)  
Amounts reclassified from accumulated other comprehensive income (loss), net of tax 13   40  
Other comprehensive income (loss), net of taxes (4,392) 1,061 (4,873) 1,669
Balance, end of period (6,537)   (6,537)  
Pre-tax components of other comprehensive income (loss) and the related income tax expense (benefit)        
Other comprehensive income (loss), before income taxes (5,571) 1,347 (6,186) 2,124
Income tax expense (benefit) (1,179) 286 (1,313) 455
Other comprehensive income (loss), net of taxes (4,392) 1,061 (4,873) 1,669
Changes in Net Unrealized Gains (Losses) on Investment Securities Having Credit Losses Recognized in the Consolidated Statement of Income [Member]        
Accumulated other comprehensive income (loss) [Roll Forward]        
Balance, beginning of period 185   186  
Other comprehensive income (loss) (OCI) before reclassifications, net of tax 0   (1)  
Amounts reclassified from accumulated other comprehensive income (loss), net of tax 0   0  
Other comprehensive income (loss), net of taxes 0 0 (1) 1
Balance, end of period 185   185  
Pre-tax components of other comprehensive income (loss) and the related income tax expense (benefit)        
Other comprehensive income (loss), before income taxes 0 0 (1) 1
Income tax expense (benefit) 0 0 0 0
Other comprehensive income (loss), net of taxes 0 0 (1) 1
Net Benefit Plan Assets and Obligations Recognized in Shareholders' Equity [Member]        
Accumulated other comprehensive income (loss) [Roll Forward]        
Balance, beginning of period (157)   (150)  
Other comprehensive income (loss) (OCI) before reclassifications, net of tax 1   1  
Amounts reclassified from accumulated other comprehensive income (loss), net of tax (2)   (9)  
Other comprehensive income (loss), net of taxes (1) 0 (8) 0
Balance, end of period (158)   (158)  
Pre-tax components of other comprehensive income (loss) and the related income tax expense (benefit)        
Other comprehensive income (loss), before income taxes (1) 0 (11) 0
Income tax expense (benefit) 0 0 (3) 0
Other comprehensive income (loss), net of taxes (1) 0 (8) 0
Net Unrealized Foreign Currency Translation [Member]        
Accumulated other comprehensive income (loss) [Roll Forward]        
Balance, beginning of period (551)   (872)  
Other comprehensive income (loss) (OCI) before reclassifications, net of tax (2)   (37)  
Amounts reclassified from accumulated other comprehensive income (loss), net of tax 0   356  
Other comprehensive income (loss), net of taxes (2) (70) 319 203
Balance, end of period (553)   (553)  
Pre-tax components of other comprehensive income (loss) and the related income tax expense (benefit)        
Other comprehensive income (loss), before income taxes (2) (72) 316 217
Income tax expense (benefit) 0 (2) (3) 14
Other comprehensive income (loss), net of taxes $ (2) $ (70) $ 319 $ 203