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Fair Value Measurements - Schedule of Quantitative Information about Level 3 Fair Value Measurements (Details) $ in Millions | Jun. 30, 2026 USD ($) | Dec. 31, 2025 USD ($)
--- | --- | ---
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Derivative assets | $ 196 | $ 175
Mortgage servicing assets excluded from OREO | 3 |
Recurring |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Derivative assets | 196 | 175
Nonrecurring |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Collateral-dependent loans | 186 | 56
Level 3 | Recurring |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Derivative assets | 1 | (2)
Insignificant level 3 assets, net of liabilities | 4 | 4
Level 3 | Nonrecurring |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Collateral-dependent loans | 186 | 56
Market comparable pricing | Level 3 | Recurring |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Loans, net of unearned income (residential) | $ 11 | $ 11
Market comparable pricing | Level 3 | Recurring | Comparability factor | Minimum |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Loans, net of unearned income (residential), measurement input | 0.7440 | 0.7430
Market comparable pricing | Level 3 | Recurring | Comparability factor | Maximum |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Loans, net of unearned income (residential), measurement input | 0.9500 | 0.9900
Market comparable pricing | Level 3 | Recurring | Comparability factor | Weighted Average |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Loans, net of unearned income (residential), measurement input | 0.8409 | 0.8499
Discounted cash flow | Level 3 | Recurring | Interest rate |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Derivative assets | $ (1) | $ (3)
Discounted cash flow | Level 3 | Recurring | Interest rate | Probability of default | Minimum |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Derivative assets, measurement input | 0.0002 | 0.0002
Discounted cash flow | Level 3 | Recurring | Interest rate | Probability of default | Maximum |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Derivative assets, measurement input | 1 | 1
Discounted cash flow | Level 3 | Recurring | Interest rate | Probability of default | Weighted Average |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Derivative assets, measurement input | 0.0420 | 0.0440
Discounted cash flow | Level 3 | Recurring | Interest rate | Loss given default | Minimum |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Derivative assets, measurement input | 0 | 0
Discounted cash flow | Level 3 | Recurring | Interest rate | Loss given default | Maximum |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Derivative assets, measurement input | 1 | 1
Discounted cash flow | Level 3 | Recurring | Interest rate | Loss given default | Weighted Average |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Derivative assets, measurement input | 0.411 | 0.485
Fair value of collateral | Level 3 | Nonrecurring |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Collateral-dependent loans | $ 186 | $ 56
Fair value of collateral | Level 3 | Nonrecurring | Credit and liquidity discount | Minimum |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Collateral-dependent loans, measurement input | 0 | 0
Fair value of collateral | Level 3 | Nonrecurring | Credit and liquidity discount | Maximum |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Collateral-dependent loans, measurement input | 0.7200 | 1.0000
Fair value of collateral | Level 3 | Nonrecurring | Credit and liquidity discount | Weighted Average |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Collateral-dependent loans, measurement input | 0.2200 | 0.4000
Appraised value | Level 3 | Nonrecurring |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
OREO and other Level 3 assets | $ 11 | $ 8

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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. 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