Master Netting and Similar Agreements – Repurchase, Reverse Repurchase, and Securities Borrowing Transactions - Schedule of Securities Purchased under Agreements to Resell and Collateral Pledged by Counterparties (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| SECURITIES PURCHASED UNDER AGREEMENTS TO RESELL | ||
| Gross amounts of recognized assets | $ 509 | $ 613 |
| Gross amounts offset in the Balance Sheets | 0 | 0 |
| Net amounts of assets presented in the Balance Sheets | 509 | 613 |
| Offsetting securities sold under agreements to repurchase | 0 | (5) |
| Securities collateral (not recognized on FHN’s Balance Sheets) | (505) | (604) |
| Net amount | $ 4 | $ 4 |
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- Definition Amount, after the effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes purchases of participations in pools of securities that are subject to a resale agreement, assets not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Amount, after effect of master netting arrangement and deduction of obligation to return financial collateral not offset and financial instrument subject to master netting arrangement not offset, of fund outstanding loaned in form of security resale agreement for purchase and resale of identical or substantially same security at date certain for specified price. Includes security purchased under agreement to resell not subject to master netting arrangement or similar agreement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of obligation to return cash collateral under master netting arrangements that have not been offset against securities purchased under agreement to resell. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of obligation to return securities collateral under master netting arrangements that have not been offset against securities purchased under agreement to resell. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, before effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of liability associated with funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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