v3.26.1
Allowance for Credit Losses (Allowance for Credit Losses Methodology) (Details) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Allowance for credit losses on loans and leases      
Balance, beginning of period $ 466 $ 425 $ 425
Provision (recapture) for credit losses on loans and leases 28 26  
Charge-offs (40) (35)  
Recoveries 5 5  
Net charge-offs (35) (30)  
Balance, end of period 459 421 466
Reserve for unfunded commitments      
Balance, beginning of period 19 16 16
Provision (recapture) for credit losses on unfunded commitments 0 1  
Balance, end of period 19 17 19
Total allowance for credit losses 478 438 485
Commercial real estate      
Allowance for credit losses on loans and leases      
Balance, beginning of period 198 154 154
Provision (recapture) for credit losses on loans and leases 14 14  
Charge-offs 0 0  
Recoveries 0 0  
Net charge-offs 0 0  
Balance, end of period 212 168 198
Reserve for unfunded commitments      
Balance, beginning of period 10 6 6
Provision (recapture) for credit losses on unfunded commitments 1 2  
Balance, end of period 11 8 10
Total allowance for credit losses 223 176  
Commercial      
Allowance for credit losses on loans and leases      
Balance, beginning of period 226 219 219
Provision (recapture) for credit losses on loans and leases 17 24  
Charge-offs (39) (33)  
Recoveries 4 4  
Net charge-offs (35) (29)  
Balance, end of period 208 214 226
Reserve for unfunded commitments      
Balance, beginning of period 7 7 7
Provision (recapture) for credit losses on unfunded commitments (1) 0  
Balance, end of period 6 7 7
Total allowance for credit losses 214 221  
Residential      
Allowance for credit losses on loans and leases      
Balance, beginning of period 34 45 45
Provision (recapture) for credit losses on loans and leases (1) (12)  
Charge-offs 0 (1)  
Recoveries 0 0  
Net charge-offs 0 (1)  
Balance, end of period 33 32 34
Reserve for unfunded commitments      
Balance, beginning of period 1 2 2
Provision (recapture) for credit losses on unfunded commitments 0 (1)  
Balance, end of period 1 1 1
Total allowance for credit losses 34 33  
Consumer & other      
Allowance for credit losses on loans and leases      
Balance, beginning of period 8 7 7
Provision (recapture) for credit losses on loans and leases (2) 0  
Charge-offs (1) (1) (5)
Recoveries 1 1  
Net charge-offs 0 0  
Balance, end of period 6 7 8
Reserve for unfunded commitments      
Balance, beginning of period 1 1 1
Provision (recapture) for credit losses on unfunded commitments 0 0  
Balance, end of period 1 1 $ 1
Total allowance for credit losses $ 7 $ 8