Changes In Accumulated Other Comprehensive Income Balances (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015		Sep. 30, 2014
Beginning Balance	$ (188,248,000)	$ (122,111,000)	$ (188,246,000)		$ (150,009,000)
Other comprehensive income before reclassifications, Net of tax	15,427,000	(11,288,000)	13,331,000		15,549,000
Amounts reclassifed from accumulated other comprehensive income, Net of tax	(3,855,000)	564,000	(1,761,000)		1,625,000
Other comprehensive income/(loss)	11,572,000	(10,724,000)	11,570,000	[1]	17,174,000	[1]
Ending Balance	(176,676,000)	(132,835,000)	(176,676,000)		(132,835,000)
Reclassification From Accumulated Other Comprehensive Income Current Period Tax	(2,400,000)	300,000	(1,100,000)		1,000,000
Unrealized Gain Loss On Securities Available For Sale [Member]
Beginning Balance	16,485,000	15,596,000	18,581,000		(11,241,000)
Other comprehensive income before reclassifications, Net of tax	15,427,000	(11,288,000)	13,331,000		15,549,000
Amounts reclassifed from accumulated other comprehensive income, Net of tax	0	0	0		0
Other comprehensive income/(loss)	15,427,000	(11,288,000)	13,331,000		15,549,000
Ending Balance	31,912,000	4,308,000	31,912,000		4,308,000
Other Comprehensive Income Loss Current Period Before Reclassification Adjustments, Tax	9,500,000	(7,000,000)	8,200,000		9,800,000
OtherComprehensiveIncomeLossTax	9,500,000	(7,000,000)	8,200,000		9,800,000
Pension And Other Postretirement Plans Costs [Member]
Beginning Balance	(204,733,000)	(137,707,000)	(206,827,000)		(138,768,000)
Other comprehensive income before reclassifications, Net of tax	0	0	0		0
Amounts reclassifed from accumulated other comprehensive income, Net of tax	(3,855,000)	564,000	(1,761,000)		1,625,000
Other comprehensive income/(loss)	(3,855,000)	564,000	(1,761,000)		1,625,000
Ending Balance	(208,588,000)	(137,143,000)	(208,588,000)		(137,143,000)
Reclassification From Accumulated Other Comprehensive Income Current Period Tax	(2,400,000)	300,000	(1,100,000)		1,000,000
OtherComprehensiveIncomeLossTax	$ (2,400,000)	$ 300,000	$ (1,100,000)		$ 1,000,000

[1] Due to the nature of the preferred stock issued by FHN and its subsidiaries, all components of Other comprehensive income/(loss) have been attributed solely to FHN as the controlling interest holder.