v3.26.1
Accumulated Other Comprehensive Income (Changes In The Components Of AOCI) (Detail) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning balance     $ (2,237)  
Other comprehensive income (loss) $ 3 $ 3 (5) $ 32
Ending balance (2,326)   (2,326)  
Accumulated Other Comprehensive Income [Member]        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning balance     (95)  
Other comprehensive income (loss)     (5)  
Ending balance (100)   (100)  
Unrealized gains (losses) on AFS, net [Member]        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning balance     (114)  
Other comprehensive income (loss)     (5)  
Ending balance (119)   (119)  
Instrument-specific credit risk of liabilities measured at fair value, net [Member]        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning balance     19  
Other comprehensive income (loss)     0  
Ending balance 19   19  
Instrument-specific credit risk of liabilities measured at fair value, net [Member] | Accumulated Other Comprehensive Income [Member]        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning balance     19  
Ending balance $ 19   $ 19