v3.26.1
Securities (Narrative) (Details)
1 Months Ended 3 Months Ended 6 Months Ended
Jan. 31, 2026
USD ($)
Jun. 30, 2026
USD ($)
Security
Jun. 30, 2025
USD ($)
Jun. 30, 2026
USD ($)
Security
Jun. 30, 2025
USD ($)
Dec. 31, 2025
USD ($)
Security
Debt and Equity Securities, FV-NI [Line Items]            
Securities with an aggregate fair value   $ 4,700,870,000   $ 4,700,870,000   $ 4,226,864,000
Securities available for sale, amortized cost   6,340,945,000   6,340,945,000   6,341,322,000
Securities classified as trading   0   0   $ 0
Restructuring costs       1,500,000,000    
Net realized loss $ (50,400,000) 0 $ 0 (98,595,000) $ 0  
Allowance for credit loss   $ 0   $ 0    
Securities that met the criteria of a credit loss event | Security   0   0    
Number of securities with market values below their cost basis | Security   588   588   604
Asset Pledged as Collateral without Right [Member]            
Debt and Equity Securities, FV-NI [Line Items]            
Securities pledged as collateral   $ 3,300,000,000   $ 3,300,000,000   $ 3,900,000,000
Available for Sale and Held to Maturity [Member]            
Debt and Equity Securities, FV-NI [Line Items]            
Amortized cost of securities excluding accrued interest   $ 31,900,000   $ 31,900,000   $ 31,700,000