Basis of Presentation and Accounting Policies	3 Months Ended
Mar. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Accounting Policies	Basis of Presentation and Accounting Policies The accompanying unaudited consolidated financial statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all information and notes necessary for complete financial statements in accordance with GAAP. In the opinion of management, the accompanying unaudited consolidated financial statements contain all significant adjustments, consisting of normal and recurring items, considered necessary for fair presentation. These interim financial statements should be read in conjunction with FHN's audited consolidated financial statements and notes in FHN's Annual Report on Form 10-K for the year ended December 31, 2022. Operating results for the interim period are not necessarily indicative of the results that may be expected for the full year. All significant intercompany balances and transactions have been eliminated in consolidation. Certain amounts reported in prior years have been reclassified to conform to the current period presentation. See the Glossary of Acronyms and Terms included in this Report for terms used herein. TD Transaction As previously disclosed, on February 27, 2022, FHN entered into an Agreement and Plan of Merger (the “TD Merger Agreement”) with The Toronto-Dominion Bank, a Canadian chartered bank (“TD”), and certain TD subsidiaries. On May 4, 2023, FHN and TD mutually terminated the TD Merger Agreement. Merger and integration planning expenses related to the transactions associated with the TD Merger Agreement are recorded in FHN’s Corporate segment. Expenses recognized during the three months ended March 31, 2023 and 2022 were $21 million and $9 million, respectively. Accounting Changes With Extended Transition Periods In March 2020, the FASB issued ASU 2020-04, “Facilitation of the Effects of Reference Rate Reform on Financial Reporting” which provides several optional expedients and exceptions to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting. The provisions of ASU 2020-04 primarily affect 1) contract modifications (e.g., loans, leases, debt, and derivatives) made in anticipation that a reference rate (e.g., LIBOR) will be discontinued and 2) the application of hedge accounting for existing relationships affected by those modifications. The provisions of ASU 2020-04 are effective upon release and apply only to contracts, hedging relationships, and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. Including the adoption of ASU 2022-06 (discussed below), the expedients and exceptions provided by ASU 2020-04 do not apply to contract modifications made and hedging relationships entered into or evaluated after December 31, 2024, except for hedging relationships existing as of December 31, 2024, that an entity has elected certain optional expedients for and that are retained through the end of the hedging relationship. FHN has identified contracts affected by reference rate reform and developed modification plans for those contracts. FHN has elected to utilize the optional expedients and exceptions provided by ASU 2020-04 for certain contract modifications that have already been implemented. For cash flow hedges that reference 1-Month USD LIBOR, FHN has applied expedients related to 1) the assumption of probability of cash flows when reference rates are changed on hedged items 2) avoiding de-designation when critical terms (i.e., reference rates) change and 3) the allowed assumption of shared risk exposure for hedged items. For its 2022 and 2023 cash flow hedges that reference 1-Month Term SOFR, FHN has applied expedients related to 1) the allowed assumption of shared risk exposure for hedged items and 2) multiple allowed assumptions of conformity between hedged items and the hedging instrument when assessing effectiveness. FHN anticipates that it will continue to utilize the expedients and exceptions for future modifications in situations where they mitigate potential accounting outcomes that do not faithfully represent management’s intent or risk management activities, consistent with the purpose of the standard. In December 2022, the FASB issued ASU 2022-06, "Deferral of the Sunset Date of Topic 848" which extends the transition window for ASU 2020-04 from December 31, 2022 to December 31, 2024, consistent with key USD LIBOR tenors continuing to be published through June 30, 2023. In January 2021, the FASB issued ASU 2021-01, "Scope" to expand the scope of ASU 2020-04 to apply to certain contract modifications that were implemented in October 2020 by derivative clearinghouses for the use of Secure Overnight Funding Rate (SOFR) in discounting, margining and price alignment for centrally cleared derivatives, including derivatives utilized in hedging relationships. ASU 2021-01 also applies to derivative contracts affected by the change in discounting convention regardless of whether they are centrally cleared (i.e., bi-lateral contracts can also be modified) and regardless of whether they reference LIBOR. ASU 2021-01 was effective immediately upon issuance with retroactive application permitted. FHN elected to retroactively apply the provisions of ASU 2021-01 because FHN's centrally cleared derivatives were affected by the change in discounting convention and because FHN has other bi-lateral derivative contracts that may be modified to conform to the use of SOFR for discounting. Adoption did not have a significant effect on FHN's reported financial condition or results of operations. Summary of Accounting Changes ASU 2022-01 In March 2022, the FASB issued ASU 2022-01, "Fair Value Hedging - Portfolio Layer Method", which will expand FHN's ability to hedge the benchmark interest rate risk of portfolios of financial interests (or beneficial interests) in a fair value hedge. The provisions of ASU 2022-01 also permit FHN to apply the same portfolio hedging method to both prepayable and non-prepayable financial assets, namely by expanding the use of the "portfolio layer" method to non-prepayable financial assets. ASU 2022-01 also permits multiple hedged layers to be designated as a single closed portfolio to achieve hedge accounting. Additionally, the ASU requires that basis adjustments must be maintained on the closed portfolio of assets as a whole, and not allocated to individual assets for active portfolio layer method hedges. ASU 2022-01 is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. FHN may utilize the provisions of ASU 2022-01 in its future hedging strategies. ASU 2022-02 In March 2022, the FASB issued ASU 2022-02, “Troubled Debt Restructurings and Vintage Disclosures” that eliminates current TDR recognition and measurement guidance and instead requires the Company to evaluate whether the modification represents a new loan or a continuation of an existing loan (which is consistent with the accounting for other loan modifications). The provisions of ASU 2022-02 also enhance existing disclosure requirements and introduces new disclosures related to certain modifications made to borrowers experiencing financial difficulty. The provisions of this ASU also require FHN to disclose current period gross write-offs of loans and leases by year of origination. ASU 2022-02 is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. For the transition method related to the recognition and measurement of TDRs, FHN elected to apply the modified retrospective transition effective January 1, 2023, resulting in a cumulative-effect reduction in ALLL of $6 million and an increase to retained earnings of $4 million, net of tax. The disclosure provisions of ASU 2022-02 are applied prospectively and presented in Note 3 – Loans and Leases and Note 4 – Allowance for Credit Losses. Accounting Changes Issued But Not Currently Effective ASU 2023-02 In March 2023, the FASB issued ASU 2023-02, “Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method” which permits investors to elect to account for their tax equity investments, regardless of the tax credit program from which the income tax credits are received, using the proportional amortization method if certain conditions are met. The proportional amortization method results in the cost of the investment being amortized in proportion to the income tax credits and other income tax benefits received, with the amortization of the investment and the income tax credits being presented net in the income statement as a component of income tax provision (benefit). Prior to ASU 2023-02, the proportional amortization method was only available to qualifying low income housing equity investments. An investor is required to make an accounting policy election to apply the proportional amortization method on a tax-credit-program-by-tax-credit-program basis. An investor that applies the proportional amortization method to qualifying tax equity investments must account for the receipt of the investment tax credits using the flow-through method, even if the entity applies the deferral method for other investment tax credits received. ASU 2023-02 also requires specific disclosures that must be applied to all investments that generate income tax credits and other income tax benefits from a tax credit program for which the entity has elected to apply the proportional amortization method. ASU 2023-02 is effective for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years. Early adoption is permitted for all entities in any interim period. If ASU 2023-02 is adopted in an interim period, it must be adopted as of the beginning of the fiscal year that includes that interim period. Adoption of ASU 2023-02 is applied on either a modified retrospective (cumulative catch up) or a retrospective (representment of prior years) basis. FHN is assessing 1) the applicability of ASU 2023-02 to its tax credit investments and 2) whether to elect the proportional amortization method for qualifying investments.

The accompanying unaudited consolidated financial statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all information and notes necessary for complete financial statements in accordance with GAAP. In the opinion of management, the accompanying unaudited consolidated financial statements contain all significant adjustments, consisting of normal and recurring items, considered necessary for fair presentation. These interim financial statements should be read in conjunction with FHN's audited consolidated financial statements and notes in FHN's Annual Report on Form 10-K for the year ended December 31, 2022. Operating results for the interim period are not necessarily indicative of the results that may be expected for the full year.

All significant intercompany balances and transactions have been eliminated in consolidation. Certain amounts reported in prior years have been reclassified to conform to the current period presentation. See the Glossary of Acronyms and Terms included in this Report for terms used herein.

TD Transaction

As previously disclosed, on February 27, 2022, FHN entered into an Agreement and Plan of Merger (the “TD Merger Agreement”) with The Toronto-Dominion Bank, a Canadian chartered bank (“TD”), and certain TD subsidiaries. On May 4, 2023, FHN and TD mutually terminated the TD Merger Agreement.

Merger and integration planning expenses related to the transactions associated with the TD Merger Agreement are recorded in FHN’s Corporate segment. Expenses recognized during the three months ended March 31, 2023 and 2022 were $21 million and $9 million, respectively.

Accounting Changes With Extended Transition Periods

In March 2020, the FASB issued ASU 2020-04, “Facilitation of the Effects of Reference Rate Reform on Financial Reporting” which provides several optional expedients and exceptions to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting. The provisions of ASU 2020-04 primarily affect 1) contract modifications (e.g., loans, leases, debt, and derivatives) made in anticipation that a reference rate (e.g., LIBOR) will be discontinued and 2) the application of hedge accounting for existing relationships affected by those modifications. The provisions of ASU

2020-04 are effective upon release and apply only to contracts, hedging relationships, and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. Including the adoption of ASU 2022-06 (discussed below), the expedients and exceptions provided by ASU 2020-04 do not apply to contract modifications made and hedging relationships entered into or evaluated after December 31, 2024, except for hedging relationships existing as of December 31, 2024, that an entity has elected certain optional expedients for and that are retained through the end of the hedging relationship.

FHN has identified contracts affected by reference rate reform and developed modification plans for those contracts. FHN has elected to utilize the optional expedients and exceptions provided by ASU 2020-04 for certain contract modifications that have already been implemented. For cash flow hedges that reference 1-Month USD LIBOR, FHN has applied expedients related to 1) the assumption of probability of cash flows when reference rates are changed on hedged items 2) avoiding de-designation when critical terms (i.e., reference rates) change and 3) the allowed assumption of shared risk exposure for hedged items. For its 2022 and 2023 cash flow hedges that reference 1-Month Term SOFR, FHN has applied expedients related to 1) the allowed assumption of shared risk exposure for hedged items and 2) multiple allowed assumptions of conformity between hedged items and the hedging instrument when assessing effectiveness. FHN anticipates that it will continue to utilize the expedients and exceptions for future modifications in situations where they mitigate potential accounting outcomes that do not faithfully represent management’s intent or risk management activities, consistent with the purpose of the standard.

In December 2022, the FASB issued ASU 2022-06, "Deferral of the Sunset Date of Topic 848" which extends the transition window for ASU 2020-04 from December 31, 2022 to December 31, 2024, consistent with key USD LIBOR tenors continuing to be published through June 30, 2023.

In January 2021, the FASB issued ASU 2021-01, "Scope" to expand the scope of ASU 2020-04 to apply to certain contract modifications that were implemented in October 2020 by derivative clearinghouses for the use of Secure Overnight Funding Rate (SOFR) in discounting, margining and price alignment for centrally cleared derivatives, including derivatives utilized in hedging relationships. ASU 2021-01 also applies to derivative contracts affected by the change in discounting convention regardless of whether they are centrally cleared (i.e., bi-lateral

contracts can also be modified) and regardless of whether they reference LIBOR. ASU 2021-01 was effective immediately upon issuance with retroactive application permitted. FHN elected to retroactively apply the provisions of ASU 2021-01 because FHN's centrally cleared derivatives were affected by the change in discounting convention and because FHN has other bi-lateral derivative contracts that may be modified to conform to the use of SOFR for discounting. Adoption did not have a significant effect on FHN's reported financial condition or results of operations.

Summary of Accounting Changes

ASU 2022-01

In March 2022, the FASB issued ASU 2022-01, "Fair Value Hedging - Portfolio Layer Method", which will expand FHN's ability to hedge the benchmark interest rate risk of portfolios of financial interests (or beneficial interests) in a fair value hedge. The provisions of ASU 2022-01 also permit FHN to apply the same portfolio hedging method to both prepayable and non-prepayable financial assets, namely by expanding the use of the "portfolio layer" method to non-prepayable financial assets. ASU 2022-01 also permits multiple hedged layers to be designated as a single closed portfolio to achieve hedge accounting. Additionally, the ASU requires that basis adjustments must be maintained on the closed portfolio of assets as a whole, and not allocated to individual assets for active portfolio layer method hedges. ASU 2022-01 is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. FHN may utilize the provisions of ASU 2022-01 in its future hedging strategies.

ASU 2022-02

In March 2022, the FASB issued ASU 2022-02, “Troubled Debt Restructurings and Vintage Disclosures” that eliminates current TDR recognition and measurement guidance and instead requires the Company to evaluate whether the modification represents a new loan or a continuation of an existing loan (which is consistent with the accounting for other loan modifications). The provisions of ASU 2022-02 also enhance existing disclosure requirements and introduces new disclosures related to certain modifications made to borrowers experiencing financial difficulty. The provisions of this ASU also require FHN to disclose current period gross write-offs of loans and leases by year of origination.

ASU 2022-02 is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. For the transition method related to the recognition and measurement of TDRs, FHN elected to apply the modified retrospective transition effective January 1, 2023, resulting in a cumulative-effect reduction in ALLL of $6 million and an increase to retained earnings of $4 million, net of tax. The disclosure provisions of ASU

2022-02 are applied prospectively and presented in Note 3 – Loans and Leases and Note 4 – Allowance for Credit Losses.

Accounting Changes Issued But Not Currently Effective

ASU 2023-02

In March 2023, the FASB issued ASU 2023-02, “Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method” which permits investors to elect to account for their tax equity investments, regardless of the tax credit program from which the income tax credits are received, using the proportional amortization method if certain conditions are met. The proportional amortization method results in the cost of the investment being amortized in proportion to the income tax credits and other income tax benefits received, with the amortization of the investment and the income tax credits being presented net in the income statement as a component of income tax provision (benefit). Prior to ASU 2023-02, the proportional amortization method was only available to qualifying low income housing equity investments. An investor is required to make an accounting policy election to apply the proportional amortization method on a tax-credit-program-by-tax-credit-program basis. An investor that applies the proportional amortization method to qualifying tax equity investments must account for the receipt of the investment tax credits using the flow-through method, even if the entity applies the deferral method for other investment tax credits received. ASU 2023-02 also requires specific disclosures that must be applied to all investments that generate income tax credits and other income tax benefits from a tax credit program for which the entity has elected to apply the proportional amortization method.

ASU 2023-02 is effective for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years. Early adoption is permitted for all entities in any interim period. If ASU 2023-02 is adopted in an interim period, it must be adopted as of the beginning of the fiscal year that includes that interim period. Adoption of ASU 2023-02 is applied on either a modified retrospective (cumulative catch up) or a retrospective (representment of prior years) basis. FHN is assessing 1) the applicability of ASU 2023-02 to its tax credit investments and 2) whether to elect the proportional amortization method for qualifying investments.