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Income Taxes (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Aug. 31, 2025 | Dec. 31, 2024
Income Tax Contingency [Line Items] |  |  |  |  |  |
Deferred Tax Assets, Net | $ 392 |  | $ 392 |  |  |
Income Tax Expense (Benefit) | 23 | $ 50 | $ 111 | $ 136 |  |
Effective Tax Rate as a Percentage of pre-tax Income (loss) |  |  | 24.90% | 25.80% |  |
Affordable housing tax credit investments | 328 |  | $ 328 |  |  | $ 221
Unfunded affordable housing tax credit commitments | 143 |  | 143 |  |  | $ 95
Columbia Banking Systems and Pacific Premier Bancorp Merger |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |
Deferred Tax Assets, Net |  |  |  |  | $ 94 |
Affordable housing tax credit investments |  |  |  |  | 75 |
Unfunded affordable housing tax credit commitments |  |  |  |  | $ 29 |
State and Local Jurisdiction |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |
Operating Loss Carryforwards | 5 |  | 5 |  |  |
State and Local Jurisdiction | Columbia Banking Systems and Pacific Premier Bancorp Merger |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |
Operating Loss Carryforwards | $ 3 |  | $ 3 |  |  |

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- Definition Amount of investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under program not meeting condition for accounting under proportional amortization method. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A + Details
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