Schedule H, Line 4i – Schedule of Assets (Held At End of Year) (Details) - EBP 002	12 Months Ended
Dec. 31, 2025 USD ($) shares
EBP, Schedule of Asset Held for Investment [Line Items]
Entity tax identification number	62-0803242
Plan number	002
Participant Loans	$ 18,737,912
Total current value	$ 1,264,929,491
Minimum
EBP, Schedule of Asset Held for Investment [Line Items]
Participant loan interest rate	3.25%
Maximum
EBP, Schedule of Asset Held for Investment [Line Items]
Participant loan interest rate	8.50%
Common/collective trust funds
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	$ 865,973,531
Mutual funds
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	58,868,999
First Horizon Corporation, common stock fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	$ 126,102,690
Number of shares/units (in shares) \| shares	5,683,172.72
Investment, Identifier [Axis]: BlackRock Equity Index Fund \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	$ 236,360,786
Investment, Identifier [Axis]: BlackRock LifePath Index 2025 L \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	0
Investment, Identifier [Axis]: BlackRock LifePath Index 2030 O \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	58,594,835
Investment, Identifier [Axis]: BlackRock LifePath Index 2035 O \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	68,681,729
Investment, Identifier [Axis]: BlackRock LifePath Index 2040 O \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	51,733,736
Investment, Identifier [Axis]: BlackRock LifePath Index 2045 O \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	57,194,219
Investment, Identifier [Axis]: BlackRock LifePath Index 2050 O \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	35,733,282
Investment, Identifier [Axis]: BlackRock LifePath Index 2055 O \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	23,796,487
Investment, Identifier [Axis]: BlackRock LifePath Index 2060 O \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	16,675,108
Investment, Identifier [Axis]: BlackRock LifePath Index 2065 O \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	6,099,870
Investment, Identifier [Axis]: BlackRock LifePath Index Retirement O \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	70,083,993
Investment, Identifier [Axis]: BlackRock MSCI ACWI ex-US Index F \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	38,262,602
Investment, Identifier [Axis]: BlackRock Russell 2500 Index Fund \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	38,988,046
Investment, Identifier [Axis]: BlackRock Total Return Bond Fund L \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	18,839,058
Investment, Identifier [Axis]: BlackRock US Debt Index Fund F \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	30,798,613
Investment, Identifier [Axis]: Dodge & Cox International \| Mutual fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	9,914,971
Investment, Identifier [Axis]: Harding Loevner International Equity \| Mutual fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	4,709,765
Investment, Identifier [Axis]: Invesco Stable Value Trust Class B1 \| Common/collective stable value fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	66,498,178
Investment, Identifier [Axis]: Loomis Sayles Large Cap Growth Trust D \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	44,244,263
Investment, Identifier [Axis]: PIMCO Diversified income fund \| Mutual fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value
Investment, Identifier [Axis]: Schwab Personal Choice Retirement Account \| Self-Directed Brokerage Account
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	128,748,181
Investment, Identifier [Axis]: T. Rowe Price Instl Large Cap Equity \| Mutual fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	44,244,263
Investment, Identifier [Axis]: Westwood SMID Cap Value Trust C \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	25,736,692
Investment, Identifier [Axis]: William Blair Small-Mid Cap Growth CIT \| Common/collective trust fund
EBP, Schedule of Asset Held for Investment [Line Items]
Investment, current value	$ 25,736,692

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection b-2

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- Definition

Amount of total assets in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, current value of investment, participant loan, and plan interest in master trust.

+ References

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- Definition

Current value of investment, excluding plan interest in master trust, in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, derivative, investment measured at net asset value per share as practical expedient, and insurance contract.

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- Definition

Amount, after deemed distribution, of participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

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- Definition

Number of shares or units of investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (3)
-Publisher DOL-EBSA

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (4)
-Publisher DOL-EBSA

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(B)
-Publisher DOL-EBSA

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (2)(i)(B)
-Publisher DOL-EBSA

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 6
-Paragraph d
-Subparagraph (1)(ii)
-Publisher DOL-EBSA

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-02(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

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- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

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- Definition

Plan number of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), in three-digit numeric format.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule II))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)
-Publisher DOL-EBSA

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule III))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (3)
-Publisher DOL-EBSA

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (4)
-Publisher DOL-EBSA

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 6
-Paragraph d
-Subparagraph (1)
-Publisher DOL-EBSA

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 6
-Paragraph d
-Subparagraph (2)
-Publisher DOL-EBSA

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(A)
-Publisher DOL-EBSA

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(C)
-Publisher DOL-EBSA

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(B)
-Publisher DOL-EBSA

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