Variable Interest Entities (Narrative) (Details)	Mar. 31, 2015 number
Variable Interest Entity [Line Items]
Number of consolidated securitization trusts with agreements to sell servicing	1
Home Equity [Member]
Variable Interest Entity [Line Items]
Number Of Securitization Trusts That Have Entered Rapid Amortization Period	2

The number of consolidated securitization trusts with agreements to sell servicing.

No definition available.

Name:	fhn_NumberOfConsolidatedSecuritizationTrustsWithAgreementsToSellServicing
Namespace Prefix:	fhn_
Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	instant