Commitments and Contingencies - Tax Credits and Amortization (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
|
| Income Tax Contingency [Line Items] | ||||
| 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 | Investments in affordable housing projects, other qualified tax credits, and other community development investments(1) | Investments in affordable housing projects, other qualified tax credits, and other community development investments(1) | Investments in affordable housing projects, other qualified tax credits, and other community development investments(1) | Investments in affordable housing projects, other qualified tax credits, and other community development investments(1) |
| Investment Program Proportional Amortization Method Applied Income Tax Credit And Other Tax Benefit Amortization Statement Of Cash Flows Extensible Enumeration Not Disclosed Flag | Investments in affordable housing projects and other qualified tax credits | Investments in affordable housing projects and other qualified tax credits | Investments in affordable housing projects and other qualified tax credits | Investments in affordable housing projects and other qualified tax credits |
| Amortization Method Applied Income Tax Credit And Other Tax Benefit Amortization Statement Of Cash Flows Extensible Enumeration Not Disclosed Flag | Investments in affordable housing projects and other qualified tax credits | Investments in affordable housing projects and other qualified tax credits | Investments in affordable housing projects and other qualified tax credits | Investments in affordable housing projects and other qualified tax credits |
| Investments in affordable housing projects | ||||
| Income Tax Contingency [Line Items] | ||||
| Investments in affordable housing projects, other qualified tax credits, and other community development investments | $ 229 | $ 210 | $ 686 | $ 630 |
| Investments in affordable housing projects and other qualified tax credits | $ 200 | $ 182 | $ 602 | $ 556 |
| 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) | Income Tax Expense (Benefit) | Income Tax Expense (Benefit) |
| Investment Program, Proportional Amortization Method, Applied, Amortization Expense, Statement of Income or Comprehensive Income [Extensible Enumeration] | Income Tax Expense (Benefit) | Income Tax Expense (Benefit) | Income Tax Expense (Benefit) | Income Tax Expense (Benefit) |
| Other Community Development Investment | ||||
| Income Tax Contingency [Line Items] | ||||
| Other community development investments | $ 2 | $ 2 | $ 6 | $ 7 |