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Variable Interest Entities - Schedule of VIE Consolidated By FHN (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Assets: |  |
Other assets | $ 4,169 | $ 4,080
Liabilities: |  |
Other liabilities | 2,382 | 2,479
Rabbi Trusts Used For Deferred Compensation Plans |  |
Assets: |  |
Other assets | 177 | 181
Liabilities: |  |
Other liabilities | $ 150 | $ 150

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