Acquisitions and Divestitures (Narrative) (Details) (USD $)					5 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012	Jun. 07, 2013 Mountain National Bank [Member] number	Jun. 07, 2013 Mountain National Bank [Member] Acquired From FDIC [Member]	Jun. 07, 2013 Mountain National Bank [Member] As Recorded by FHN [Member]
Business Acquisition [Line Items]
Acquisition date						Jun. 07, 2013
Business Acquisition, Name of Acquired Entity					Mountain National Bank
Number Of Bank Branches					12
Assets acquired						$ 452,000,000
Loans acquired						249,000,000
Deposits assumed						362,000,000
Asset discount						33,000,000
Goodwill	$ 141,943,000	$ 141,943,000	$ 134,242,000	$ 134,242,000			$ 7,700,000