v3.25.4
Fair Value Measurement - Schedule of Roll Forward of Financial Instruments (Details) - Significant Unobservable Inputs (Level 3)
$ in Millions
 12 Months Ended
Dec. 31, 2024
USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]  
Balance at Beginning of Year $ 1,152
Total Gains / (Losses) Recorded in Earnings (69)
Purchases / Originations 241
Sales (1,194)
Transfers In (Out) (71)
Balance at End of Year $ 59
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Noninterest Income
Mortgage servicing rights  
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]  
Balance at Beginning of Year $ 1,111
Total Gains / (Losses) Recorded in Earnings (75)
Purchases / Originations 184
Sales (1,194)
Transfers In (Out) 0
Balance at End of Year 26
Private Label collateralized mortgage obligations  
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]  
Balance at Beginning of Year 32
Total Gains / (Losses) Recorded in Earnings 1
Purchases / Originations 0
Sales 0
Transfers In (Out) 0
Balance at End of Year 33
Rate lock commitments  
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]  
Balance at Beginning of Year 9
Total Gains / (Losses) Recorded in Earnings 5
Purchases / Originations 57
Sales 0
Transfers In (Out) (71)
Balance at End of Year $ 0