v3.26.1
Securitizations and Variable Interest Entities, Income Statement Impacts for Affordable Housing and Renewable Energy Tax Credit Investments (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Involvement With Tax Credit VIEs Textual [Abstract]      
Total loans $ 1,016,787 $ 913,842 $ 986,167
Investment program, proportional amortization method, policy election [true false] true true  
VIEs that we do not consolidate [Member]      
Variable Interest Entity [Line Items]      
Income (loss) before income tax expense, proportional amortization method investments $ 56 $ 57  
Investment Program, Proportional Amortization Method, Applied, Non-Income-Tax-Related Activity and Other Return, Statement of Income or Comprehensive Income [Extensible Enumeration] Other Other  
Investment Program Proportional Amortization Method Applied NonIncome Tax Related Activity And Other Return Statement Of Cash Flows Extensible Enumeration Not Disclosed Flag true true  
Income (loss) before income tax expense, equity method investments $ (34) $ (49)  
Net income (loss) before income tax expense 22 8  
Income tax expense (benefit), proportional amortization of investments 874 708  
Income tax expense (benefit), income tax credits and other income tax benefits (1,174) (956)  
Net expense (benefit) recognized within income tax expense (300) (248)  
Net income (loss) related to affordable housing and renewable energy tax credit investments $ 322 $ 256  
Involvement With Tax Credit VIEs Textual [Abstract]      
Investment program commitment, payment period 3 years   3 years
Investment Program, Proportional Amortization Method, Applied, Amortization Expense, Statement of Income or Comprehensive Income [Extensible Enumeration] Income tax expense (benefit) Income tax expense (benefit)  
Investment Program, Proportional Amortization Method, Elected, Income Tax Credit and Other Income Tax Benefit, before Amortization, Statement of Income or Comprehensive Income [Extensible Enumeration] Income tax expense (benefit) Income tax expense (benefit)  
Investment Program, Proportional Amortization Method, Elected, Income Tax Credit and Other Income Tax Benefit, after Amortization, Statement of Income or Comprehensive Income [Extensible Enumeration] Income tax expense (benefit) Income tax expense (benefit)  
Investment program proportional amortization method elected income tax credit and other income amortization statement of cash flows extensible enumeration not disclosed flag true true  
Investment program proportional amortization method elected income tax credit and other income tax benefit before amortization statement of cash flows extensible enumeration not disclosed flag true true  
Investment Program, Proportional Amortization Method, Elected, Income Tax Credit and Other Income Tax Benefit, after Amortization, Statement of Cash Flows Extensible Enumeration Not Disclosed Flag true true  
VIEs that we do not consolidate [Member] | Accounting method, investment tax credit, deferral      
Variable Interest Entity [Line Items]      
Income (loss) before income tax expense, equity method investments $ (140) $ (111)  
VIEs that we do not consolidate [Member] | Accrued expenses and other liabilities [Member]      
Involvement With Tax Credit VIEs Textual [Abstract]      
Investment program, commitment 5,600   $ 5,700
VIEs that we do not consolidate [Member] | Tax credit structures [Member]      
Involvement With Tax Credit VIEs Textual [Abstract]      
Maximum exposure to loss 30,600   31,100
VIEs that we do not consolidate [Member] | Tax credit structures [Member] | Unfunded equity and loan commitment [Member]      
Involvement With Tax Credit VIEs Textual [Abstract]      
Maximum exposure to loss 7,800   7,800
VIEs that we do not consolidate [Member] | Carrying value [Member] | Tax credit structures [Member]      
Involvement With Tax Credit VIEs Textual [Abstract]      
Equity securities 20,900   21,200
Total loans $ 1,800   $ 2,000