Fair Values of Assets and Liabilities - Fair Value Option (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Fair Value Disclosures [Abstract] | ||
| Fair value carrying amount, total loans | $ 2,645 | $ 2,353 |
| Contractual principal outstanding, total loans | 2,625 | 2,325 |
| Carrying amount over (under) contractual principal outstanding, total loans | 20 | 28 |
| Fair value carrying amount, time deposits | 13 | 718 |
| Contractual principal outstanding, time deposits | 13 | 718 |
| Carrying amount over (under) contractual principal outstanding, time deposits | 0 | 0 |
| Long-term debt | 1,904 | 1,414 |
| Contractual principal outstanding, long-term debt | 1,948 | 1,419 |
| Carrying amount over (under) contractual principal outstanding, long-term debt | (44) | (5) |
| Fair value, nonaccrual loans | 1 | 1 |
| Contractual principal outstanding, nonaccrual loans | 1 | 1 |
| Fair value, loans 90 days or more past due | 2 | 5 |
| Contractual principal outstanding, loans 90 days or more past due | $ 2 | $ 5 |
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- Definition Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of long-term debt instruments that have contractual principal amounts and for which the fair value option has been elected. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition This item represents the aggregate fair value of loans held as assets that are in nonaccrual status for which the fair value option has been elected, if the entity's policy is to recognize interest income separately from other changes in fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Fair value portion of mortgage loans held-for-sale. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Fair Value Option Loans Held As Assets Aggregate Amount In Nonaccrual Status Aggregate Unpaid Principal No definition available.
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- Definition Fair Value Option Loans Held As Assets Contractual Principal No definition available.
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- Definition Fair Value Option Loans Held As Assets Ninety Days Or More Past Due Aggregate Unpaid Principal No definition available.
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- Definition Fair Value Option, Long-Term Debt, Contractual Principal Outstanding No definition available.
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- Definition Fair value option time deposits carrying amount over under contractual principal outstanding. No definition available.
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- Definition Fair value option time deposits contractual principal outstanding. No definition available.
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