Variable Interest Entities (Summary Of VIE Consolidated By FHN) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011
Assets:
Cash and due from banks	$ 382,601		$ 469,879	$ 330,931
Loans, net of unearned income	16,197,046		16,708,582	16,185,763
Allowance for loan losses	261,934	265,218	276,963	321,051	346,016	384,351
Total net loans (Restricted - $.1 billion on June 30, 2013; June 30, 2012; and December 31, 2012)	15,935,112		16,431,619	15,864,712
Other assets	1,604,889		1,670,840	1,848,890
Total assets (Restricted - $.1 billion on June 30, 2013; June 30, 2012; and December 31, 2012)	25,133,274		25,520,140	25,492,955
Liabilities:
Term borrowings	1,800,255		2,226,482	2,294,224
Other liabilities	587,635		743,933	782,044
Total liabilities (Restricted - $.1 billion on June 30, 2013; June 30, 2012; and December 31, 2012)	22,586,923		23,010,934	22,978,549
On Balance Sheet Consumer Loan Securitizations [Member]
Assets:
Cash and due from banks	1,206			0
Loans, net of unearned income	109,222			129,319
Allowance for loan losses	3,839			6,046
Total net loans (Restricted - $.1 billion on June 30, 2013; June 30, 2012; and December 31, 2012)	105,383			123,273
Other assets	1,687			2,606
Total assets (Restricted - $.1 billion on June 30, 2013; June 30, 2012; and December 31, 2012)	108,276			125,879
Liabilities:
Term borrowings	99,487			120,553
Other liabilities	21			21
Total liabilities (Restricted - $.1 billion on June 30, 2013; June 30, 2012; and December 31, 2012)	99,508			120,574
Rabbi Trusts Used For Deferred Compensation Plans [Member]
Assets:
Other assets	61,447			59,650
Total assets (Restricted - $.1 billion on June 30, 2013; June 30, 2012; and December 31, 2012)	61,447			59,650
Liabilities:
Other liabilities	47,507			48,991
Total liabilities (Restricted - $.1 billion on June 30, 2013; June 30, 2012; and December 31, 2012)	$ 47,507			$ 48,991