ACCUMULATED OTHER COMPREHENSIVE (LOSS) INCOME - Schedule of Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
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| Accumulated Other Comprehensive Income (Loss) [Line Items] | ||
| Pretax | $ (74) | $ 134 |
| Income Taxes | 2 | (51) |
| Net of Income Taxes | (72) | 83 |
| Unrealized loss on securities available for sale | ||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | ||
| Pretax | (349) | (162) |
| Income Taxes | 73 | 25 |
| Net of Income Taxes | (276) | (137) |
| Unrealized loss on securities available for sale transferred to held to maturity | ||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | ||
| Pretax | (5) | (5) |
| Income Taxes | 1 | 1 |
| Net of Income Taxes | (4) | (4) |
| Defined benefit pension items | ||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | ||
| Pretax | 280 | 282 |
| Income Taxes | (72) | (72) |
| Net of Income Taxes | 208 | 210 |
| Unrealized gain on cash flow hedge derivatives | ||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | ||
| Pretax | 0 | 19 |
| Income Taxes | 0 | (5) |
| Net of Income Taxes | $ 0 | $ 14 |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, attributable to parent. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners). No definition available.
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- Definition Amount of tax expense (benefit) allocated to accumulated other comprehensive income (loss) attributable to parent. No definition available.
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