Variable Interest Entities (Summary Of VIE Consolidated By FHN) (Details) (USD $)	Mar. 31, 2015		Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Assets:
Cash and due from banks	$ 282,800,000		$ 349,171,000	$ 450,270,000
Loans, net of unearned income	16,732,123,000	[1]	16,230,166,000	15,119,461,000
Allowance for loan losses	228,328,000		232,448,000	247,246,000	253,809,000
Total net loans	16,503,795,000		15,997,718,000	14,872,215,000
Other assets	1,419,204,000		1,385,572,000	1,429,704,000
Total assets	25,715,888,000		25,668,187,000	23,936,836,000
Liabilities:
Term borrowings	1,573,215,000		1,880,105,000	1,507,048,000
Other liabilities	795,878,000		649,359,000	628,420,000
Total liabilities	23,216,631,000		23,086,597,000	21,404,324,000
On Balance Sheet Consumer Loan Securitizations [Member]
Assets:
Cash and due from banks	872,000			0
Loans, net of unearned income	71,565,000			86,685,000
Allowance for loan losses	341,000			1,954,000
Total net loans	71,224,000			84,731,000
Other assets	242,000			888,000
Total assets	72,338,000			85,619,000
Liabilities:
Term borrowings	60,914,000			77,119,000
Other liabilities	4,000			5,000
Total liabilities	60,918,000			77,124,000
Rabbi Trusts Used For Deferred Compensation Plans [Member]
Assets:
Other assets	68,356,000			64,217,000
Total assets	68,356,000			64,217,000
Liabilities:
Other liabilities	52,349,000			50,423,000
Total liabilities	$ 52,349,000			$ 50,423,000

[1] (b) March 31, 2015 includes $28.0 million of held-to-maturity consumer mortgage loans secured by residential real estate properties in process of foreclosure.