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v3.24.3

Allowance for Credit Losses - Rollforward of Allowance for Credit Losses (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023 | Dec. 31, 2022
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | $ 821 | $ 737 | $ 773 | $ 685 | $ 685 |
Charge-offs | (33) | (104) | (128) | (159) |  |
Recoveries | 9 | 9 | 30 | 25 |  |
Provision for credit losses and remaining unfunded commitments | 26 | 118 | 148 | 215 |  |
Ending balance | 823 | 760 | 823 | 760 | 773 | $ 685
Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance | 66 | 90 | 83 | 87 | 87 |
Provision for remaining unfunded commitments | 9 | (8) | (8) | (5) |  |
Ending balance | 75 | 82 | 75 | 82 | 83 | $ 87
Allowance for credit losses | 898 | 842 | 898 | 842 |  |
Loans and leases | 62,445 |  | 62,445 |  | $ 61,292 |
Accounting Standards Update [Extensible List] |  |  |  |  | Accounting Standards Update 2023-02 | Accounting Standards Update 2022-02
Accounting Standards Update 2022-02 |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance |  |  |  | (6) | $ (6) |
Ending balance |  |  |  |  |  | $ (6)
Commercial: | Commercial, financial and industrial |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | 344 | 326 | 339 | 308 | 308 |
Charge-offs | (12) | (91) | (64) | (124) |  |
Recoveries | 4 | 5 | 19 | 12 |  |
Provision for credit losses and remaining unfunded commitments | 16 | 95 | 58 | 138 |  |
Ending balance | 352 | 335 | 352 | 335 | 339 | 308
Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance | 44 | 55 | 49 | 55 | 55 |
Provision for remaining unfunded commitments | 11 | (6) | 6 | (6) |  |
Ending balance | 55 | 49 | 55 | 49 | 49 | 55
Allowance for credit losses | 407 | 384 | 407 | 384 |  |
Loans and leases | 33,092 |  | 33,092 |  | 32,633 |
Commercial: | Commercial, financial and industrial | Single Company |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Charge-offs |  |  |  | (72) |  |
Commercial: | Commercial, financial and industrial | Paycheck Protection Plan |  |  |  |  |  |
Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Loans and leases | 15 | 35 | 15 | 35 | 29 |
Commercial: | Commercial, financial and industrial | Accounting Standards Update 2022-02 |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance |  |  |  | 1 | 1 |
Ending balance |  |  |  |  |  | 1
Commercial: | Commercial Real Estate |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | 221 | 159 | 172 | 146 | 146 |
Charge-offs | (15) | (5) | (47) | (15) |  |
Recoveries | 1 | 1 | 1 | 2 |  |
Provision for credit losses and remaining unfunded commitments | 11 | 14 | 92 | 36 |  |
Ending balance | 218 | 169 | 218 | 169 | 172 | 146
Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance | 10 | 24 | 22 | 22 | 22 |
Provision for remaining unfunded commitments | (2) | (3) | (14) | (1) |  |
Ending balance | 8 | 21 | 8 | 21 | 22 | 22
Allowance for credit losses | 226 | 190 | 226 | 190 |  |
Loans and leases | 14,705 |  | 14,705 |  | 14,216 |
Commercial: | Commercial Real Estate | Accounting Standards Update 2022-02 |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance |  |  |  | 0 | 0 |
Ending balance |  |  |  |  |  | 0
Commercial: | Credit Card and Other |  |  |  |  |  |
Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Loans and leases | 184 |  | 184 |  | 180 |
Consumer: |  |  |  |  |  |
Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Loans and leases | 13,961 |  | 13,961 |  | 13,650 |
Consumer: | Consumer Real Estate |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | 231 | 221 | 233 | 200 | 200 |
Charge-offs | (1) | (1) | (2) | (3) |  |
Recoveries | 3 | 2 | 6 | 7 |  |
Provision for credit losses and remaining unfunded commitments | (3) | 6 | (7) | 31 |  |
Ending balance | 230 | 228 | 230 | 228 | 233 | 200
Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance | 12 | 11 | 12 | 10 | 10 |
Provision for remaining unfunded commitments | 0 | 1 | 0 | 2 |  |
Ending balance | 12 | 12 | 12 | 12 | 12 | 10
Allowance for credit losses | 242 | 240 | 242 | 240 |  |
Loans and leases | 13,961 |  | 13,961 |  | 13,650 |
Consumer: | Consumer Real Estate | Accounting Standards Update 2022-02 |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance |  |  |  | (7) | (7) |
Ending balance |  |  |  |  |  | (7)
Consumer: | Credit Card and Other |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance | 25 | 31 | 29 | 31 | 31 |
Charge-offs | (5) | (7) | (15) | (17) |  |
Recoveries | 1 | 1 | 4 | 4 |  |
Provision for credit losses and remaining unfunded commitments | 2 | 3 | 5 | 10 |  |
Ending balance | 23 | 28 | 23 | 28 | 29 | 31
Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance | 0 | 0 | 0 | 0 | 0 |
Provision for remaining unfunded commitments | 0 | 0 | 0 | 0 |  |
Ending balance | 0 | 0 | 0 | 0 | 0 | 0
Allowance for credit losses | 23 | $ 28 | 23 | 28 |  |
Loans and leases | $ 687 |  | $ 687 |  | 793 |
Consumer: | Credit Card and Other | Accounting Standards Update 2022-02 |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |
Beginning balance |  |  |  | $ 0 | $ 0 |
Ending balance |  |  |  |  |  | $ 0

X
- Definition Financing Receivable And Off-Balance Sheet Credit Loss Liability, Allowance For Credit Loss, Excluding Accrued Interest + References No definition available. + Details
Name: | fhn_FinancingReceivableAndOffBalanceSheetCreditLossLiabilityAllowanceForCreditLossExcludingAccruedInterest
Namespace Prefix: | fhn_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
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