Variable Interest Entities (Summary Of VIE Consolidated By FHN) (Details) (USD $)	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
Assets:
Cash and due from banks	$ 292,687,000		$ 349,216,000	$ 395,631,000
Loans, net of unearned income	15,812,017,000		15,389,074,000	15,408,556,000
Allowance for loan losses	238,641,000	243,628,000	253,809,000	255,710,000	261,934,000	276,963,000
Total net loans	15,573,376,000		15,135,265,000	15,152,846,000
Other assets	1,356,356,000		1,685,384,000	1,637,139,000
Total assets (Restricted - $.1 billion on September 30, 2014; September 30, 2013; and December 31, 2013)	23,986,787,000		23,789,833,000	23,858,753,000
Liabilities:
Term borrowings	1,491,138,000		1,739,859,000	1,771,288,000
Other liabilities	545,678,000		603,898,000	770,773,000
Total liabilities (Restricted - $.1 billion on September 30, 2014; September 30, 2013; and December 31, 2013)	21,364,846,000		21,289,082,000	21,425,460,000
On Balance Sheet Consumer Loan Securitizations [Member]
Assets:
Cash and due from banks	300,000			1,494,000
Loans, net of unearned income	81,111,000			104,052,000
Allowance for loan losses	812,000			3,217,000
Total net loans	80,299,000			100,835,000
Other assets	438,000			1,435,000
Total assets (Restricted - $.1 billion on September 30, 2014; September 30, 2013; and December 31, 2013)	81,037,000			103,764,000
Liabilities:
Term borrowings	70,720,000			93,700,000
Other liabilities	4,000			19,000
Total liabilities (Restricted - $.1 billion on September 30, 2014; September 30, 2013; and December 31, 2013)	70,724,000			93,719,000
Rabbi Trusts Used For Deferred Compensation Plans [Member]
Assets:
Other assets	66,290,000			63,238,000
Total assets (Restricted - $.1 billion on September 30, 2014; September 30, 2013; and December 31, 2013)	66,290,000			63,238,000
Liabilities:
Other liabilities	50,477,000			49,469,000
Total liabilities (Restricted - $.1 billion on September 30, 2014; September 30, 2013; and December 31, 2013)	$ 50,477,000			$ 49,469,000