v3.26.3
FAIR VALUES OF ASSETS AND LIABILITIES - Level 3 Roll Forward (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Jun. 30, 2026
Dec. 31, 2025
Jun. 30, 2025
Dec. 31, 2024
Level 3 Assets Roll Forward:                
Transfers into Level 3     $ 0          
Transfers out of Level 3     (39)          
Derivative instruments                
Opening balance $ 0 $ 3 0 $ 3 $ 9 $ 3 $ 7 $ 2
Transfers into Level 3 0 0   0        
Transfers out of Level 3 (11) (14)   (31)        
Included in earnings       $ 0        
Included in earnings, location       Interest and Dividend Income, Operating        
Included in OCI 0 0 0 $ 0        
Purchases/originations 0 0 0 0        
Repayments 0 0 0 0        
Settlements 1 2 4 8        
Closing balance 0 3 0 3        
Change in unrealized gains (losses) for the period included in earnings for assets held at end of the reporting date (10) (1) (6) 4        
Mortgage banking income                
Derivative instruments                
Included in earnings   $ 12   $ 34        
Included in earnings, location   Noninterest income   Noninterest income        
Other noninterest income                
Derivative instruments                
Included in earnings $ (1) $ (4)   $ (10)        
Included in earnings, location Noninterest income Noninterest income   Noninterest income        
Cadence                
Derivative instruments                
Purchases/originations     1          
Location, Statement of Income, Balance [Axis]: us-gaap:InterestAndDividendIncomeOperating                
Derivative instruments                
Included in earnings $ 0   $ 32          
Included in earnings, location Interest and Dividend Income, Operating   Interest and Dividend Income, Operating          
Location, Statement of Income, Balance [Axis]: us-gaap:NoninterestIncome                
Derivative instruments                
Included in earnings $ 2   $ (1)          
Included in earnings, location Noninterest income   Noninterest income          
MSRs                
Level 3 Assets Roll Forward:                
Opening balance $ 752 $ 567 $ 593 $ 573        
Transfers into Level 3 0 0 0 0        
Transfers out of Level 3 0 0 0 0        
Total gains (losses) for the period:                
Included in earnings       $ 0        
Included in earnings, location       Interest and Dividend Income, Operating        
Included in OCI 0 0 0 $ 0        
Purchases/originations 35 27 103 67        
Repayments 0 0 0 0        
Settlements (22) (17) (67) (48)        
Closing balance 837 576 837 576 752 593 567 573
Change in unrealized gains (losses) for the period included in earnings for assets held at end of the reporting date 72 (1) 68 (16)        
MSRs | Mortgage banking income                
Total gains (losses) for the period:                
Included in earnings   $ (1)   $ (16)        
Included in earnings, location   Noninterest income   Noninterest income        
MSRs | Other noninterest income                
Total gains (losses) for the period:                
Included in earnings $ 0 $ 0   $ 0        
Included in earnings, location Noninterest income Noninterest income   Noninterest income        
MSRs | Cadence                
Total gains (losses) for the period:                
Purchases/originations     140          
MSRs | Location, Statement of Income, Balance [Axis]: us-gaap:InterestAndDividendIncomeOperating                
Total gains (losses) for the period:                
Included in earnings $ 0   $ 0          
Included in earnings, location Interest and Dividend Income, Operating   Interest and Dividend Income, Operating          
MSRs | Location, Statement of Income, Balance [Axis]: us-gaap:NoninterestIncome                
Total gains (losses) for the period:                
Included in earnings $ 72   $ 68          
Included in earnings, location Noninterest income   Noninterest income          
Municipal securities                
Level 3 Assets Roll Forward:                
Opening balance $ 4,565 $ 4,067 $ 4,061 $ 3,954        
Transfers into Level 3 0 0 0 0        
Transfers out of Level 3 0 0 0 0        
Total gains (losses) for the period:                
Included in earnings       $ (1)        
Included in earnings, location       Interest and Dividend Income, Operating        
Included in OCI (84) 35 (116) $ 52        
Purchases/originations 275 160 1,264 799        
Repayments 0 0 0 0        
Settlements (369) (172) (822) (714)        
Closing balance 4,387 4,090 4,387 4,090 4,565 4,061 4,067 3,954
Change in unrealized gains (losses) for the period included in earnings for assets held at end of the reporting date (88) 34 (122) 48        
Municipal securities | Mortgage banking income                
Total gains (losses) for the period:                
Included in earnings   $ 0   $ 0        
Included in earnings, location   Noninterest income   Noninterest income        
Municipal securities | Other noninterest income                
Total gains (losses) for the period:                
Included in earnings $ 0 $ 0   $ 0        
Included in earnings, location Noninterest income Noninterest income   Noninterest income        
Municipal securities | Cadence                
Total gains (losses) for the period:                
Purchases/originations     0          
Municipal securities | Location, Statement of Income, Balance [Axis]: us-gaap:InterestAndDividendIncomeOperating                
Total gains (losses) for the period:                
Included in earnings $ 0   $ 0          
Included in earnings, location Interest and Dividend Income, Operating   Interest and Dividend Income, Operating          
Municipal securities | Location, Statement of Income, Balance [Axis]: us-gaap:NoninterestIncome                
Total gains (losses) for the period:                
Included in earnings $ 0   $ 0          
Included in earnings, location Noninterest income   Noninterest income          
Private-label CMO                
Level 3 Assets Roll Forward:                
Opening balance $ 20 $ 21 $ 19 $ 21        
Transfers into Level 3 0 0 0 0        
Transfers out of Level 3 0 0 0 0        
Total gains (losses) for the period:                
Included in earnings       $ 0        
Included in earnings, location       Interest and Dividend Income, Operating        
Included in OCI 0 0 0 $ 0        
Purchases/originations 0 0 0        
Repayments 0 0 0 0        
Settlements 0 2 1 2        
Closing balance 20 23 20 23 20 19 21 21
Change in unrealized gains (losses) for the period included in earnings for assets held at end of the reporting date 0 0 0 0        
Private-label CMO | Mortgage banking income                
Total gains (losses) for the period:                
Included in earnings   $ 0   $ 0        
Included in earnings, location   Noninterest income   Noninterest income        
Private-label CMO | Other noninterest income                
Total gains (losses) for the period:                
Included in earnings $ 0 $ 0   $ 0        
Included in earnings, location Noninterest income Noninterest income   Noninterest income        
Private-label CMO | Cadence                
Total gains (losses) for the period:                
Purchases/originations     0          
Private-label CMO | Location, Statement of Income, Balance [Axis]: us-gaap:InterestAndDividendIncomeOperating                
Total gains (losses) for the period:                
Included in earnings $ 0   $ 0          
Included in earnings, location Interest and Dividend Income, Operating   Interest and Dividend Income, Operating          
Private-label CMO | Location, Statement of Income, Balance [Axis]: us-gaap:NoninterestIncome                
Total gains (losses) for the period:                
Included in earnings $ 0   $ 0          
Included in earnings, location Noninterest income   Noninterest income          
Asset-backed securities                
Level 3 Assets Roll Forward:                
Opening balance $ 43 $ 38 $ 28 $ 49        
Transfers into Level 3 0 0 0 0        
Transfers out of Level 3 0 0 0 0        
Total gains (losses) for the period:                
Included in earnings       $ 0        
Included in earnings, location       Interest and Dividend Income, Operating        
Included in OCI 0 0 0 $ 0        
Purchases/originations 0 0 24        
Repayments 0 0 0 0        
Settlements (15) 0 (24) (11)        
Closing balance 28 38 28 38 43 28 38 49
Change in unrealized gains (losses) for the period included in earnings for assets held at end of the reporting date 0 0 0 0        
Asset-backed securities | Mortgage banking income                
Total gains (losses) for the period:                
Included in earnings   $ 0   $ 0        
Included in earnings, location   Noninterest income   Noninterest income        
Asset-backed securities | Other noninterest income                
Total gains (losses) for the period:                
Included in earnings $ 0 $ 0   $ 0        
Included in earnings, location Noninterest income Noninterest income   Noninterest income        
Asset-backed securities | Cadence                
Total gains (losses) for the period:                
Purchases/originations     0          
Asset-backed securities | Location, Statement of Income, Balance [Axis]: us-gaap:InterestAndDividendIncomeOperating                
Total gains (losses) for the period:                
Included in earnings $ 0   $ 0          
Included in earnings, location Interest and Dividend Income, Operating   Interest and Dividend Income, Operating          
Asset-backed securities | Location, Statement of Income, Balance [Axis]: us-gaap:NoninterestIncome                
Total gains (losses) for the period:                
Included in earnings $ 0   $ 0          
Included in earnings, location Noninterest income   Noninterest income          
Loans held for investment                
Level 3 Assets Roll Forward:                
Opening balance $ 62 $ 62 $ 62 $ 61        
Transfers into Level 3 5 3 9 7        
Transfers out of Level 3 0 0 0 0        
Total gains (losses) for the period:                
Included in earnings       $ 0        
Included in earnings, location       Interest and Dividend Income, Operating        
Included in OCI 0 0 0 $ 0        
Purchases/originations 0 0 0 0        
Repayments (1) (2) (5) (5)        
Settlements 0 0 0 0        
Closing balance 65 63 65 63 $ 62 $ 62 $ 62 $ 61
Change in unrealized gains (losses) for the period included in earnings for assets held at end of the reporting date 0 0 0 0        
Loans held for investment | Mortgage banking income                
Total gains (losses) for the period:                
Included in earnings   $ 0   $ 0        
Included in earnings, location   Noninterest income   Noninterest income        
Loans held for investment | Other noninterest income                
Total gains (losses) for the period:                
Included in earnings $ 0 $ 0   $ 0        
Included in earnings, location Noninterest income Noninterest income   Noninterest income        
Loans held for investment | Cadence                
Total gains (losses) for the period:                
Purchases/originations     0          
Loans held for investment | Location, Statement of Income, Balance [Axis]: us-gaap:InterestAndDividendIncomeOperating                
Total gains (losses) for the period:                
Included in earnings $ (1)   $ (1)          
Included in earnings, location Interest and Dividend Income, Operating   Interest and Dividend Income, Operating          
Loans held for investment | Location, Statement of Income, Balance [Axis]: us-gaap:NoninterestIncome                
Total gains (losses) for the period:                
Included in earnings $ 0   $ 0          
Included in earnings, location Noninterest income   Noninterest income