v3.26.1
Loans And The Allowance For Credit Losses(Aging and Non-Accrual Performance for Modifications to Troubled Borrowers (Details) - USD ($)
$ in Millions
Mar. 31, 2026
Mar. 31, 2025
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period $ 414 $ 421
Commercial    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 157 96
Investor Real Estate    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 54 118
Consumer    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 203 207
Current    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 227 294
Current | Commercial    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 61 74
Current | Investor Real Estate    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 28 64
Current | Consumer    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 138 156
Financial Asset, 30 to 89 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 30 29
Financial Asset, 30 to 89 Days Past Due | Commercial    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 3
Financial Asset, 30 to 89 Days Past Due | Investor Real Estate    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 0
Financial Asset, 30 to 89 Days Past Due | Consumer    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 30 26
Financial Asset, Equal to or Greater than 90 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 25 15
Financial Asset, Equal to or Greater than 90 Days Past Due | Commercial    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due | Investor Real Estate    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 0
Financial Asset, Equal to or Greater than 90 Days Past Due | Consumer    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 25 15
Non-performing [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 132 83
Non-performing [Member] | Commercial    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 96 19
Non-performing [Member] | Investor Real Estate    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 26 54
Non-performing [Member] | Consumer    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 10 10
Commercial And Industrial [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 132 93
Commercial And Industrial [Member] | Current    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 39 72
Commercial And Industrial [Member] | Financial Asset, 30 to 89 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 3
Commercial And Industrial [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 0
Commercial And Industrial [Member] | Non-performing [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 93 18
Commercial Real Estate Mortgage - Owner-Occupied [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 25 3
Commercial Real Estate Mortgage - Owner-Occupied [Member] | Current    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 22 2
Commercial Real Estate Mortgage - Owner-Occupied [Member] | Financial Asset, 30 to 89 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 0
Commercial Real Estate Mortgage - Owner-Occupied [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 0
Commercial Real Estate Mortgage - Owner-Occupied [Member] | Non-performing [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 3 1
Commercial investor real estate mortgage [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 54 118
Commercial investor real estate mortgage [Member] | Current    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 28 64
Commercial investor real estate mortgage [Member] | Financial Asset, 30 to 89 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 0
Commercial investor real estate mortgage [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 0
Commercial investor real estate mortgage [Member] | Non-performing [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 26 54
Residential First Mortgage [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 188 185
Residential First Mortgage [Member] | Current    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 126 138
Residential First Mortgage [Member] | Financial Asset, 30 to 89 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 30 25
Residential First Mortgage [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 25 15
Residential First Mortgage [Member] | Non-performing [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 7 7
Home Equity Lines of Credit[Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 5 11
Home Equity Lines of Credit[Member] | Current    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 4 10
Home Equity Lines of Credit[Member] | Financial Asset, 30 to 89 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 0
Home Equity Lines of Credit[Member] | Financial Asset, Equal to or Greater than 90 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 0
Home Equity Lines of Credit[Member] | Non-performing [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 1 1
Home Equity Loan [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 10 11
Home Equity Loan [Member] | Current    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 8 8
Home Equity Loan [Member] | Financial Asset, 30 to 89 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 1
Home Equity Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period 0 0
Home Equity Loan [Member] | Non-performing [Member]    
Financing Receivable, Modifications [Line Items]    
Modifications to Troubled Borrowers, modified in the previous 12-month period $ 2 $ 2