v3.26.1
INVESTMENT SECURITIES - Narrative (Details)
shares in Thousands
1 Months Ended 3 Months Ended 12 Months Ended
Apr. 30, 2026
USD ($)
Mar. 31, 2026
USD ($)
security
shares
Mar. 31, 2025
USD ($)
Dec. 31, 2025
USD ($)
Jan. 24, 2024
shares
Schedule of Investments [Line Items]          
Debt securities, available-for-sale, accrued Interest   $ 184,000,000   $ 157,000,000  
Debt Securities, held-to-maturity, accrued interest   18,000,000   20,000,000  
Write off of accrued interest receivable   $ 0 $ 0    
Debt securities, held-to-maturity, threshold period past due   30 days      
Securities past due   $ 9,542,000,000   9,647,000,000  
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, number of positions | security   300      
Investment securities available for sale, allowance for credit loss   $ 0      
Securities, nonaccrual   $ 0   $ 0  
Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List Not Disclosed Flag [Extensible Enumeration]   available for sale and held to maturity debt securities   available for sale and held to maturity debt securities  
Purchase Money Note          
Schedule of Investments [Line Items]          
Partial prepayment   $ 2,500,000,000      
Purchase Money Note | Subsequent Event          
Schedule of Investments [Line Items]          
Partial prepayment $ 500,000,000        
Asset Pledged as Collateral          
Schedule of Investments [Line Items]          
Investment securities, aggregate carrying value, pledged as collateral   $ 3,590,000,000   $ 3,890,000,000  
Government sponsored enterprise-issued mortgage-backed securities, government agency securities, or U.S. treasury securities          
Schedule of Investments [Line Items]          
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, number of positions | security   285      
Corporate bonds          
Schedule of Investments [Line Items]          
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, number of positions | security   15      
Total Past Due          
Schedule of Investments [Line Items]          
Securities past due   $ 0   $ 0  
Visa, Inc | Class B common stock          
Schedule of Investments [Line Items]          
Investment owned (in shares) | shares   354      
Visa, Inc | Class B-1          
Schedule of Investments [Line Items]          
Investment owned (in shares) | shares         354