v3.25.2
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Basis Adjustments for Hedged Items) (Details) - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Derivative Instruments, Gain (Loss) [Line Items]    
Cumulative amount of fair value hedging adjustment included in the carrying amount of the hedged items $ 29.0  
Investment securities 10,406.0 $ 10,601.0
Amount of hedging 4,500.0  
Fair Value Hedging    
Derivative Instruments, Gain (Loss) [Line Items]    
Investment securities 9,800.0  
Fair Value Hedging | Hedges of fixed-rate assets    
Derivative Instruments, Gain (Loss) [Line Items]    
Par value of hedged items 11,473.0 11,388.0
Carrying amount of hedged assets 11,299.0 11,099.0
Cumulative amount of fair value hedging adjustment included in the carrying amount of the hedged items (174.0) (289.0)
Fair Value Hedging | Hedges of fixed-rate liabilities    
Derivative Instruments, Gain (Loss) [Line Items]    
Par value of hedged liabilities (500.0) (500.0)
Carrying amount of hedged liabilities (509.0) (493.0)
Cumulative amount of fair value hedging adjustment included in the carrying amount of the hedged items $ (9.0) $ 7.0