v3.26.1
MORTGAGE BANKING AND OTHER SERVICED LOANS - Economic Assumptions Used to Estimate Value of MSRs (Details) - USD ($)
$ in Millions
6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value [Abstract]    
Fair value $ 1,482 $ 1,455
Weighted average life (years) 8 years 2 months 12 days 8 years
Weighted average constant prepayment rate 6.60% 7.00%
Weighted average option adjusted spread 5.53% 5.88%
Minimum    
Servicing Assets at Fair Value [Line Items]    
Sensitivity analysis, basis spread 10.00%  
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value [Abstract]    
Decline in fair value from 10% adverse change $ 38 $ 38
Decline in fair value from 10% adverse change $ 38 40
Maximum    
Servicing Assets at Fair Value [Line Items]    
Sensitivity analysis, basis spread 20.00%  
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value [Abstract]    
Decline in fair value from 20% adverse change $ 73 73
Decline in fair value from 20% adverse change $ 75 $ 80