v3.26.1
Allowance for Loan Losses - Education Loans - Age Analysis of Past Due Loans Delinquencies (Parenthetical) (Details)
$ in Millions
Jun. 30, 2026
USD ($)
Financing Receivable, Past Due [Line Items]  
Loans held for sale $ 528
Private Education Loans [Member]  
Financing Receivable, Past Due [Line Items]  
Loans held for sale $ 528