Value of capital securities

No definition available.

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Namespace Prefix:	fhn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Interest rate for capital securities stated in the contractual debt agreement.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- 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)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Details

Name:	us-gaap_StatementClassOfStockAxis=fhn_CapitalSecuritiesSeriesBMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SubordinatedDebenturesSubjectToMandatoryRedemptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=fhn_FirstTenneseeCapitalIiMember
Namespace Prefix:
Data Type:	na
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Period Type:

Term Borrowings (Narrative) (Details) - USD ($)	12 Months Ended
Term Borrowings (Narrative) (Details) - USD ($)	Dec. 31, 2004	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Term borrowings		$ 1,315,176,000	$ 1,880,105,000
First Horizon National Corporation \| Capital Securities Series B
Debt Instrument [Line Items]
Debt Instrument Maturity Date	Apr. 15, 2034
First Horizon National Corporation \| Subordinated Debentures Subject To Mandatory Redemption [Member] \| Capital Securities Series B
Debt Instrument [Line Items]
Term borrowings	$ 206,000,000
Debt Instrument Interest Rate Stated Percentage	6.30%
First Tennesee Capital II \| Capital Securities Series B
Debt Instrument [Line Items]
Capital securities value	$ 200,000,000
Interest rate of capital securities	6.30%
Debt Instrument Maturity Date	Apr. 15, 2034