v3.26.1
Borrowings - Narrative (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2026
Dec. 31, 2025
Line of Credit Facility [Line Items]    
Other short-term borrowings $ 12,486 $ 6,913
Weighted-average interest rate of short-term borrowings 3.98% 4.09%
Secured Uncommitted Lines Of Credit    
Line of Credit Facility [Line Items]    
Other short-term borrowings $ 4,800 $ 3,800
CSC Commercial Paper Notes | 5.0 Billion Commercial Paper Notes    
Line of Credit Facility [Line Items]    
Capacity of allowable commercial paper note issuance $ 5,000  
Maturity term 270 days  
Commercial paper $ 4,700 1,900
Discounts on commercial paper 39 32
CS & Co Unsecured Commercial Paper Notes | 10.0 Billion Commercial Paper Notes | Charles Schwab & Co., Inc.    
Line of Credit Facility [Line Items]    
Capacity of allowable commercial paper note issuance $ 10,000  
Maturity term 270 days  
Commercial paper $ 0  
Federal Reserve Bank Advances    
Line of Credit Facility [Line Items]    
Other short-term borrowings 0 0
Total borrowing capacity 28,600 29,300
Repurchase Agreements    
Line of Credit Facility [Line Items]    
Other short-term borrowings 3,000 1,300
Line of Credit | Uncommitted Lines Of Credit With External Banks    
Line of Credit Facility [Line Items]    
Other short-term borrowings 0 0
Total borrowing capacity 1,900  
Line of Credit | Secured Uncommitted Lines Of Credit    
Line of Credit Facility [Line Items]    
Other short-term borrowings 4,800 3,800
Federal Home Loan Bank Advances | Secured Credit Facility    
Line of Credit Facility [Line Items]    
Borrowings outstanding 0 $ 1,900
Weighted average interest rate   3.90%
Total borrowing capacity $ 33,500 $ 74,200