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Sale of mortgage servicing rights during the year.

+ References

No definition available.

+ Details

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- Definition

Reductions of servicing asset at fair value due to the exercise of clean up calls related to proprietary securitization trusts that had previously been securitized with servicing retained. Upon exercise, the associated mortgage loans were repurchased and consolidated, and the remaining MSR associated with these loans was derecognized.

+ References

No definition available.

+ Details

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- Definition

Decrease in servicing assets subsequently measured at fair value resulting from loan payments received.

+ References

No definition available.

+ Details

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Namespace Prefix:	fhn_
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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122625-111746

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- Definition

The net Increase or Decrease in fair value as a result of changes in the inputs, assumptions, or model used to calculate the fair value of servicing assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 3

-Subparagraph (a)(4)(i)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122625-111746

+ Details

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- Definition

The net Increase or Decrease in fair value as a result of other changes that are not additions, disposals, or a result of change in the inputs, assumptions, or model used to calculate the fair value of servicing assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 3

-Subparagraph (a)(4)(ii)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122625-111746

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Period Type:	duration

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Mortgage Servicing Rights (Summary Of Changes In Capitalized MSR) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Participating Mortgage Loans [Line Items]
Fair value, beginning balance	$ 72,793,000us-gaap_ServicingAssetAtFairValueAmount	$ 114,311,000us-gaap_ServicingAssetAtFairValueAmount
Reductions due to sales of MSRs	(70,204,000)fhn_MortgageServicingRightsSale	(39,633,000)fhn_MortgageServicingRightsSale	0fhn_MortgageServicingRightsSale
Reductions due to loan payments		(21,572,000)
Reductions due to exercise of cleanup calls		(495,000)
Changes in fair value due to:
Changes in valuation model inputs or assumptions		20,184,000
Other changes in fair value		(2,000)
Fair value, ending balance	2,517,000us-gaap_ServicingAssetAtFairValueAmount	72,793,000us-gaap_ServicingAssetAtFairValueAmount	114,311,000us-gaap_ServicingAssetAtFairValueAmount
First Liens [Member]
Participating Mortgage Loans [Line Items]
Fair value, beginning balance		111,314,000
Reductions due to sales of MSRs		(39,633,000)
Reductions due to loan payments		(20,938,000)
Reductions due to exercise of cleanup calls		(495,000)
Changes in fair value due to:
Changes in valuation model inputs or assumptions		20,184,000
Other changes in fair value		(91,000)
Fair value, ending balance		70,341,000
Second Liens [Member]
Participating Mortgage Loans [Line Items]
Fair value, beginning balance		196,000
Reductions due to sales of MSRs		0
Reductions due to loan payments		(80,000)
Reductions due to exercise of cleanup calls		0
Changes in fair value due to:
Changes in valuation model inputs or assumptions		0
Other changes in fair value		45,000
Fair value, ending balance		161,000
Home Equity [Member]
Participating Mortgage Loans [Line Items]
Fair value, beginning balance		2,801,000
Reductions due to sales of MSRs		0
Reductions due to loan payments		(554,000)
Reductions due to exercise of cleanup calls		0
Changes in fair value due to:
Changes in valuation model inputs or assumptions		0
Other changes in fair value		44,000
Fair value, ending balance		$ 2,291,000