Collateral received.

No definition available.

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- Definition

Derivative liabilities related to sale of a portion of Visa class B shares.

+ References

No definition available.

+ Details

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- Definition

Hedged Amount of Foreign Currency Denominated Loans

+ References

No definition available.

+ Details

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- Definition

Gross amount of debt matured.

+ References

No definition available.

+ Details

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624258-113959

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- Definition

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226016-175313

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (d)(2)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

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-Paragraph 8

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=d3e41678-113959

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

+ Details

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- Definition

Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (c)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section 55

-Paragraph 10

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-Name Accounting Standards Codification

-Topic 210

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-Paragraph 9

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- Definition

Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

+ Details

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- Definition

Fair value as of the balance sheet date of all derivative assets designated as interest rate fair value hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

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- Definition

Fair value as of the balance sheet date of all derivative liabilities designated as interest rate fair value hedging instruments.

+ References

+ Details

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- Definition

Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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- Definition

Amount of gain (loss) resulting from the difference between the acquisition price and the selling price or fair value of trading assets and trading liabilities, conducted separately from customer trading activities. Includes, but is not limited to, changes in fair value of trading assets and trading liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4F

-Subparagraph (a)

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-Name Accounting Standards Codification

-Topic 942

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-Section S99

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-Subparagraph (SX 210.9-04.13(e))

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-Paragraph 3

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Derivatives (Narrative) (Details) (USD $)	3 Months Ended
Derivatives (Narrative) (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Jan. 31, 2015	Dec. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Collateral cash receivables	$ 93,400,000	$ 101,800,000
Collateral cash payables	56,800,000	82,500,000
Total trading revenues	53,500,000us-gaap_TradingGainsLosses	49,600,000us-gaap_TradingGainsLosses
Other Long-term Debt	1,573,215,000us-gaap_OtherLongTermDebt	1,507,048,000us-gaap_OtherLongTermDebt		1,880,105,000us-gaap_OtherLongTermDebt
Hedged amount of foreign currency denominated loans	3,800,000	800,000
Borrowings matured			304,000,000fhn_MaturityOfDebtAmount
Visa Class B Shares [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liabilities related to sale	5,000,000	4,900,000
Long Term Debt Hedged With Fair Value Interest Rate Derivatives Using Shortcut Method [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net fair value of interest rate derivatives hedging	12,000,000	34,100,000
Other Long-term Debt	250,000,000	554,000,000
Long Term Debt Hedged With Fair Value Interest Rate Derivatives Using Long Haul Method [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net fair value of interest rate derivatives hedging	6,900,000	16,000,000
Other Long-term Debt	500,000,000	500,000,000
Long Term Debt Hedged With Fair Value Interest Rate Derivatives Using Long Haul Method [Member] \| First Tennessee Bank National Association [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net fair value of interest rate derivatives hedging	5,500,000
Other Long-term Debt	400,000,000
Subordinated Debentures Subject To Mandatory Redemption Amounts Redeemed [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net fair value of interest rate derivatives hedging subordinated debt	2,700,000	16,400,000
Other Long-term Debt	200,000,000	200,000,000
Additional Derivative Agreements [Member] \| Derivative Instruments With Accelerated Termination Provisions [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Collateral received	173,500,000	200,000,000
Securities posted collateral	25,900,000	27,800,000
Net fair value of derivative assets with adjustable posting thresholds	107,300,000	121,900,000
Net fair value of derivative liabilities with adjustable posting thresholds	21,100,000	22,600,000
Additional Derivative Agreements [Member] \| Derivative Instruments With Adjustable Collateral Posting Thresholds [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Collateral received	173,500,000	200,000,000
Securities posted collateral	84,700,000	92,500,000
Net fair value of derivative assets with adjustable posting thresholds	107,300,000	121,900,000
Net fair value of derivative liabilities with adjustable posting thresholds	$ 84,500,000	$ 90,300,000