Entity tax identification number Entity Tax Identification Number Rollovers EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Rollover Maximum Maximum [Member] Forfeited nonvested account, decrease from administrative expense EBP, Forfeited Nonvested Account, Decrease from Administrative Expense Legal Entity [Axis] Legal Entity [Axis] Maximum loans received per participant during twelve-month period, one primary residence loan EBP, Maximum Loans Received Per Participant During Twelve-Month Period, One Primary Residence Loan EBP, Maximum Loans Received Per Participant During Twelve-Month Period, One Primary Residence Loan Statistical Measurement [Domain] Statistical Measurement [Domain] EBP, Description of Plan [Table] EBP, Description of Plan [Table] EBP, Participant Contribution, Type [Domain] EBP, Participant Contribution, Type [Domain] EBP, Participant Contribution, Type [Domain] Mutual funds Mutual Fund [Member] Common/collective trust funds EBP, Self Directed Brokerage Account and Common Collective Trust Fund [Member] EBP, Self Directed Brokerage Account and Common Collective Trust Fund Employer contribution, annual fixed rate contribution, percentage EBP, Employer Contribution, Participant Contribution Matched, Percentage EBP, Employer Contribution, Participant Contribution Matched, Percentage EBP, Related Party and Party-in-Interest Transactions [Table] EBP, Related Party and Party-in-Interest Transactions [Table] Maximum participant contribution EBP, Participant Contribution, Pretax, Maximum Annual Compensation to Total Compensation, Percentage Requisite service period, minimum working hours EBP, Requisite Service Period, Minimum Working Hours EBP, Requisite Service Period, Minimum Working Hours Total deductions EBP, Change in Net Asset Available for Benefit, Decrease Self directed brokerage account EBP, Self-Directed Brokerage Account [Member] Note receivable from participant, account, maximum borrowing, amount EBP, Note Receivable from Participant, Account, Maximum Borrowing, Amount Fair Value Measurements EBP, Investment, Fair Value and NAV [Text Block] Note receivable from participant, account, minimum borrowing, amount EBP, Note Receivable from Participant, Account, Minimum Borrowing, Amount Expense accrual EBP, Accrued Expense Total investments – at fair value EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value Level 1 Fair Value, Inputs, Level 1 [Member] EBP, Investment, Fair Value and NAV [Abstract] Note receivable from participant, account, primary residence, borrowing term EBP, Note Receivable From Participant, Account, Primary Residence, Borrowing Term EBP, Note Receivable From Participant, Account, Primary Residence, Borrowing Term Total assets EBP, Asset Maximum loans outstanding per participant, two general purpose loans EBP, Maximum Loans Outstanding Per Participant, Two General Purpose Loans EBP, Maximum Loans Outstanding Per Participant, Two General Purpose Loans Statistical Measurement [Axis] Statistical Measurement [Axis] Additions: EBP, Change in Net Asset Available for Benefit, Increase [Abstract] EBP, Statement of Change in Net Asset Available for Benefit [Table] EBP, Statement of Change in Net Asset Available for Benefit [Table] Benefit Payments EBP, Payment to Participant [Policy Text Block] EBP, Trustee EBP, Trustee [Member] Total liabilities EBP, Liability Company Matching Contributions Company Matching Contributions [Member] Company Matching Contributions Amendment Flag Amendment Flag Basis of Accounting EBP, Basis of Accounting [Policy Text Block] EBP, Schedule of Asset Held for Investment [Table] EBP, Schedule of Asset Held for Investment [Table] Number of shares/units (in shares) EBP, Investment, Number of Shares EBP, Description of Plan and Accounting Change [Abstract] Receivables: EBP, Receivable [Abstract] Schedule of Investments at Fair Value and NAV EBP, Investment, Fair Value and NAV [Table Text Block] Schwab Personal Choice Retirement Account [Member] Schwab Personal Choice Retirement Account [Member] Schwab Personal Choice Retirement Account EBP, Contribution, Participating Employer [Domain] EBP, Contribution, Participating Employer [Domain] Employer contribution vesting service period EBP, Employer Contribution Vesting Service Period EBP, Employer Contribution Vesting Service Period EBP, Schedule of Delinquent Participant Contribution [Abstract] Investments [Domain] Investments [Domain] Use of Estimates EBP, Use of Estimate [Policy Text Block] EBP, Related Party and Party-in-Interest [Domain] EBP, Related Party and Party-in-Interest [Domain] Schedule H, Line 4a - Schedule of Delinquent Participant Contributions Schedule H, Line 4i – Schedule of Assets (Held At End of Year) EBP, Schedule of Asset Held for Investment [Text Block] Cover [Abstract] EBP, Contribution, Participating Employer [Axis] EBP, Contribution, Participating Employer [Axis] Risks and Uncertainties Concentration of Participant Investments EBP, Risk and Uncertainty [Text Block] Employer EBP, Change in Net Asset Available for Benefit, Increase from Employer Contribution, Cash EBP, Schedule of Delinquent Participant Contribution [Line Items] EBP, Schedule of Delinquent Participant Contribution [Line Items] EBP, Related Party and Party-in-Interest [Axis] EBP, Related Party and Party-in-Interest [Axis] Minimum Minimum [Member] Pre-Tax and Roth Contributions Pre-Tax and Roth Contributions [Member] Pre-Tax and Roth Contributions Interest income on notes receivable from participants EBP, Change in Net Asset Available for Benefit, Increase from Interest Income on Note Receivable from Participant Investment Type [Axis] Investment Type [Axis] Total contributions EBP, Change in Net Asset Available for Benefit, Increase from Contribution Participants EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Excluding Rollover EBP, Participant Contribution, Type [Axis] EBP, Participant Contribution, Type [Axis] EBP, Participant Contribution, Type Liabilities: Liabilities [Abstract] Net appreciation in investments EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Gain (Loss) on Investment Interest and dividend income EBP, Change in Net Asset Available for Benefit, Increase from Interest and Dividend Income on Investment EBP, Description of Plan [Line Items] EBP, Description of Plan [Line Items] Plan number EBP, Plan Number Investment, Issuer Name [Axis] Investment, Issuer Name [Axis] EBP, Investment, Fair Value and NAV [Line Items] EBP, Investment, Fair Value and NAV [Line Items] Plan Description Plan Termination EBP, Description of Plan [Text Block] EBP, Statement of Change in Net Asset Available for Benefit [Line Items] EBP, Statement of Change in Net Asset Available for Benefit [Line Items] EBP, Statement of Net Asset Available for Benefit [Table] EBP, Statement of Net Asset Available for Benefit [Table] EBP, Schedule of Asset Held for Investment [Line Items] EBP, Schedule of Asset Held for Investment [Line Items] Contributions EBP, Contribution [Policy Text Block] Employer contribution vesting percentage EBP, Employer Contribution Vesting Percentage EBP, Employer Contribution Vesting Percentage First Horizon Corporation, common stock fund Company common stock fund EBP, Employer, Common Stock [Member] Black Rock Equity Index Black Rock Equity Index [Member] Black Rock Equity Index Part Time Employees Part Time Employees [Member] Part Time Employees EBP, Schedule of Asset Held for Investment [Abstract] EBP, Accounting Policy [Table] EBP, Accounting Policy [Table] Total additions EBP, Change in Net Asset Available for Benefit, Increase Investment income (loss): EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Income (Loss) on Investment [Abstract] Investment, Identifier [Axis] Investment, Identifier [Axis] EBP, Employer Contribution, Type [Domain] EBP, Employer Contribution, Type [Domain] EBP, Employer Contribution, Type [Domain] Administrative expenses EBP, Change in Net Asset Available for Benefit, Decrease from Administrative Expense Total current value EBP, Asset Held for Investment Employer Non-Elective Contributions Employer Non-Elective Contributions [Member] Employer Non-Elective Contributions Document Information [Line Items] Document Information [Line Items] EBP, Risk and Uncertainty [Line Items] EBP, Risk and Uncertainty [Line Items] EBP, Risk and Uncertainty [Table] EBP, Risk and Uncertainty [Table] EBP, Statement of Change in Net Asset Available for Benefit [Abstract] Level 2 Fair Value, Inputs, Level 2 [Member] Requisite service period EBP, Requisite Service Period EBP, Requisite Service Period Maximum loans outstanding per participant, two different loans, one primary residence loan EBP, Maximum Loans Outstanding Per Participant, Two Different Loans, One Primary Residence Loan EBP, Maximum Loans Outstanding Per Participant, Two Different Loans, One Primary Residence Loan Investment in employer common stock to assets, percentage EBP, Investment, Employer, Common Stock, to Total Asset, Percentage Company Savings Contributions Company Savings Contributions [Member] Company Savings Contributions EBP, Tax Status [Table] EBP, Tax Status [Table] Net increase EBP, Change in Net Asset Available for Benefit, Increase (Decrease) Related-Party and Party-In-Interest Transactions EBP, Related Party and Party-in-Interest Transactions [Text Block] EBP, Related Party and Party-in-Interest Transactions [Abstract] EBP, Accounting Policy, Accounting Standard Update, and Change in Accounting Principle [Abstract] Total receivables EBP, Receivable Employer contributions EBP, Employer Contribution, Receivable Participant contribution, automatic, deferral rate EBP, Participant Contribution, Automatic, Deferral Rate Investments – at fair value: (Notes 2 and 8) EBP, Investment, Fair Value [Abstract] Benefits paid to participants or beneficiaries EBP, Change in Net Asset Available for Benefit, Decrease from Payment to Participant Investment, current value EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Current Value Long Term Part Time Employees Long Term Part Time Employees [Member] Long Term Part Time Employees Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Assets: Assets [Abstract] EBP, Statement of Net Asset Available for Benefit [Abstract] EBP, Accounting Policy [Line Items] EBP, Accounting Policy [Line Items] EBP, Tax Status [Abstract] Cash EBP, Noninterest-Bearing Cash Administrative Expense EBP, Expense [Policy Text Block] Participant Loans EBP, Asset Held for Investment, Participant Loan, after Deemed Distribution Investment Valuation and Income Recognition EBP, Investment [Policy Text Block] Total Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] Document Type Document Type EBP, Requisite Service Period, Number Of Consecutive 12-Month Periods EBP, Requisite Service Period, Number Of Consecutive 12-Month Periods EBP, Requisite Service Period, Number Of Consecutive 12-Month Periods Entity Central Index Key Entity Central Index Key EBP, Employer Contribution, Type [Axis] EBP, Employer Contribution, Type [Axis] EBP, Employer Contribution, Type Stable value fund (common/collective trust) Stable value fund (common/collective trust) [Member] Stable value fund (common/collective trust) Participant loan interest rate EBP, Asset Held for Investment, Participant Loan, Interest Rate EBP 002 EBP 002 [Member] EBP 002 Common/collective trust funds Common Collective Trust [Member] Net assets available for benefits: EBP, Net Asset Available for Benefit [Abstract] EBP, Tax Status [Line Items] EBP, Tax Status [Line Items] EBP, Risk and Uncertainty [Abstract] EBP, Subsequent Event [Table] EBP, Subsequent Event [Table] Deductions: EBP, Change in Net Asset Available for Benefit, Decrease [Abstract] Maximum loans outstanding per participant, two different loans, one general purpose loan EBP, Maximum Loans Outstanding Per Participant, Two Different Loans, One General Purpose Loan EBP, Maximum Loans Outstanding Per Participant, Two Different Loans, One General Purpose Loan Forfeited nonvested account, decrease from employer contribution EBP, Forfeited Nonvested Account, Decrease from Employer Contribution Notes receivable from participants EBP, Note Receivable from Participant EBP, Minimum Age At End Of Most Recent 12-Month Period For Eligibility EBP, Minimum Age At End Of Most Recent 12-Month Period For Eligibility EBP, Minimum Age At End Of Most Recent 12-Month Period For Eligibility Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Summary of Significant Accounting Policies EBP, Summary of Accounting Policy [Text Block] Entity Registrant Name Entity Registrant Name Investment concentration of plan net assets, percentage EBP, Risk and Uncertainty, Concentration of Investment at Fair Value to Net Assets, Percentage EBP, Subsequent Event [Abstract] Subsequent Events Evaluation EBP, Subsequent Event [Text Block] Delinquent Participant Contributions EBP, Schedule of Delinquent Participant Contribution [Text Block] EBP, Schedule of Delinquent Participant Contribution [Table] EBP, Schedule of Delinquent Participant Contribution [Table] Tax Status of Plan EBP, Tax Status [Text Block] Note receivable from participant, account, maximum borrowing, to total account, percentage EBP, Note Receivable from Participant, Account, Maximum Borrowing, to Total Account, Percentage EBP, Subsequent Event [Line Items] EBP, Subsequent Event [Line Items] Document Information [Table] Document Information [Table] Investment, Issuer Name [Domain] Investment, Issuer Name [Domain] Note Receivable from Participants EBP, Note Receivable from Participant [Policy Text Block] Net investment income (loss) EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Income (Loss) on Investment Maximum loans received per participant during twelve-month period, one other loan EBP, Maximum Loans Received Per Participant During Twelve-Month Period, One Other Loan EBP, Maximum Loans Received Per Participant During Twelve-Month Period, One Other Loan Note receivable from participant, general loan, borrowing term EBP, Note Receivable From Participant, General Loan, Borrowing Term EBP, Note Receivable From Participant, General Loan, Borrowing Term NAV redemption period EBP, Fair Value, Investment, NAV, Redemption, Notice Period EBP, Related Party and Party-in-Interest Transactions [Line Items] EBP, Related Party and Party-in-Interest Transactions [Line Items] Level 3 Fair Value, Inputs, Level 3 [Member] Delinquent participant contribution, not corrected EBP, Schedule of Delinquent Participant Contribution, Not Corrected Net assets available for benefits Beginning of year End of year EBP, Net Asset Available for Benefit Entity [Domain] Entity [Domain] Contributions: EBP, Change in Net Asset Available for Benefit, Increase from Contribution [Abstract] Employer contribution, employee minimum years of service requisite to access matching contributions EBP, Employer Contribution, Employee Minimum Years Of Service Requisite To Access Matching Contributions EBP, Employer Contribution, Employee Minimum Years Of Service Requisite To Access Matching Contributions Forfeited nonvested account EBP, Forfeited Nonvested Account Employer contribution, matching percentage EBP, Employer Contribution, Matching Percentage Non-Roth After Tax Contributions Non-Roth After Tax Contributions [Member] Non-Roth After Tax Contributions NAV Fair Value Measured at Net Asset Value Per Share [Member] EBP, Investment, Fair Value and NAV [Table] EBP, Investment, Fair Value and NAV [Table] EBP, Statement of Net Asset Available for Benefit [Line Items] EBP, Statement of Net Asset Available for Benefit [Line Items]