v3.25.2
Other Comprehensive Income (Loss) - Components of Other Comprehensive Income (Loss) Including Reclassification Adjustments by Income Statement (Detail) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Mar. 31, 2025
Dec. 31, 2024
Mar. 31, 2024
Dec. 31, 2023
Accumulated Other Comprehensive Income (Loss), before Tax [Roll Forward]                
Pretax total accumulated other comprehensive income (loss), beginning balance $ (671) $ (2,316) $ (1,809) $ (2,053)        
Pretax total accumulated other comprehensive income (loss), Investment securities 558 (85) 1,666 (499)        
Pretax total accumulated other comprehensive income (loss), before reclassifications 558 (85) 1,666 (499)        
Pretax total accumulated other comprehensive income (loss), Net realized gains (losses) on securities 16 (221) (14) (372)        
Pretax total accumulated other comprehensive income (loss), Interest expense (1)   (1)          
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax 0   0          
After tax total accumulated other comprehensive income (loss), Interest expense (1)   (1)          
Total reclassification adjustment for amounts realized in net income, pre tax 15 (221) (15) (372)        
Total other comprehensive income (loss), pre tax 543 136 1,681 (127)        
Pretax total accumulated other comprehensive income (loss), ending balance (128) (2,180) (128) (2,180)        
Stockholders' Equity Attributable to Parent 32,604 23,340 32,604 23,340   $ 25,591    
Accumulated Other Comprehensive Income (Loss), Tax [Roll Forward]                
Total tax (provision) benefit, beginning balance 147 492 386 437        
Total tax (provision) benefit, Investment securities (117) 18 (350) 105        
Total tax (provision) benefit, before reclassifications (117) 18 (350) 105        
Total tax (provision) benefit, Net realized gains (losses) on securities (3) 46 3 78        
Total reclassification adjustment for amounts realized in net income, Total tax (provision) benefit (3) 46 3 78        
Total other comprehensive income (loss), tax (provision) benefit (114) (28) (353) 27        
Total tax (provision) benefit, ending balance 33 464 33 464        
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]                
After tax total accumulated other comprehensive income (loss), beginning balance (524) (1,824) (1,423) (1,616)        
After tax total accumulated other comprehensive income (loss), Investment securities 441 (67) 1,316 (394)        
After tax total accumulated other comprehensive income (loss), before reclassifications 441 (67) 1,316 (394)        
After tax total accumulated other comprehensive income (loss), Net realized gains (losses) on securities 13 (175) (11) (294)        
Total reclassification adjustment for amounts realized in net income, after tax 12 (175) (12) (294)        
Total other comprehensive income (loss), after tax 429 108 1,328 (100)        
After tax total accumulated other comprehensive income (loss), ending balance (95) (1,716) (95) (1,716)        
Total net unrealized gains (losses) on securities                
Accumulated Other Comprehensive Income (Loss), before Tax [Roll Forward]                
After tax total accumulated other comprehensive income (loss), Interest expense 0   0          
Stockholders' Equity Attributable to Parent (81) (1,701) (81) (1,701) $ (509) (1,408) $ (1,809) $ (1,601)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]                
After tax total accumulated other comprehensive income (loss), Investment securities 441 (67) 1,316 (394)        
After tax total accumulated other comprehensive income (loss), before reclassifications 441 (67) 1,316 (394)        
After tax total accumulated other comprehensive income (loss), Net realized gains (losses) on securities 13 (175) (11) (294)        
Total reclassification adjustment for amounts realized in net income, after tax 13 (175) (11) (294)        
Total other comprehensive income (loss), after tax 428 108 1,327 (100)        
Net unrealized losses on forecasted transactions                
Accumulated Other Comprehensive Income (Loss), before Tax [Roll Forward]                
After tax total accumulated other comprehensive income (loss), Interest expense (1)   (1)          
Stockholders' Equity Attributable to Parent (13) (14) (13) (14) (14) (14) (14) (14)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]                
After tax total accumulated other comprehensive income (loss), Investment securities 0 0 0 0        
After tax total accumulated other comprehensive income (loss), before reclassifications 0 0 0 0        
After tax total accumulated other comprehensive income (loss), Net realized gains (losses) on securities 0 0 0 0        
Total reclassification adjustment for amounts realized in net income, after tax (1) 0 (1) 0        
Total other comprehensive income (loss), after tax 1 0 1 0        
Foreign currency translation adjustment                
Accumulated Other Comprehensive Income (Loss), before Tax [Roll Forward]                
After tax total accumulated other comprehensive income (loss), Interest expense 0   0          
Stockholders' Equity Attributable to Parent (1) (1) (1) (1) $ (1) $ (1) $ (1) $ (1)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]                
After tax total accumulated other comprehensive income (loss), Investment securities 0 0 0 0        
After tax total accumulated other comprehensive income (loss), before reclassifications 0 0 0 0        
After tax total accumulated other comprehensive income (loss), Net realized gains (losses) on securities 0 0 0 0        
Total reclassification adjustment for amounts realized in net income, after tax 0 0 0 0        
Total other comprehensive income (loss), after tax $ 0 $ 0 $ 0 $ 0