Derivatives (Derivatives Associated With Legacy Mortgage Servicing Activities) (Details) (USD $) In Thousands, unless otherwise specified					3 Months Ended				6 Months Ended				3 Months Ended				6 Months Ended				3 Months Ended				6 Months Ended				3 Months Ended				6 Months Ended
	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2012 Forwards And Futures [Member] Retained Interests Hedging [Member] Hedging Instruments [Member]		Jun. 30, 2011 Forwards And Futures [Member] Retained Interests Hedging [Member] Hedging Instruments [Member]		Jun. 30, 2012 Forwards And Futures [Member] Retained Interests Hedging [Member] Hedging Instruments [Member]		Jun. 30, 2011 Forwards And Futures [Member] Retained Interests Hedging [Member] Hedging Instruments [Member]		Jun. 30, 2012 Interest Rate Swaps And Swaptions [Member] Retained Interests Hedging [Member] Hedging Instruments [Member]		Jun. 30, 2011 Interest Rate Swaps And Swaptions [Member] Retained Interests Hedging [Member] Hedging Instruments [Member]		Jun. 30, 2012 Interest Rate Swaps And Swaptions [Member] Retained Interests Hedging [Member] Hedging Instruments [Member]		Jun. 30, 2011 Interest Rate Swaps And Swaptions [Member] Retained Interests Hedging [Member] Hedging Instruments [Member]		Jun. 30, 2012 Mortgage Servicing Rights [Member] Retained Interests Hedging [Member] Hedged Items [Member]		Jun. 30, 2011 Mortgage Servicing Rights [Member] Retained Interests Hedging [Member] Hedged Items [Member]		Jun. 30, 2012 Mortgage Servicing Rights [Member] Retained Interests Hedging [Member] Hedged Items [Member]		Jun. 30, 2011 Mortgage Servicing Rights [Member] Retained Interests Hedging [Member] Hedged Items [Member]		Jun. 30, 2012 Other Retained Interests [Member] Retained Interests Hedging [Member] Hedged Items [Member]		Jun. 30, 2011 Other Retained Interests [Member] Retained Interests Hedging [Member] Hedged Items [Member]		Jun. 30, 2012 Other Retained Interests [Member] Retained Interests Hedging [Member] Hedged Items [Member]		Jun. 30, 2011 Other Retained Interests [Member] Retained Interests Hedging [Member] Hedged Items [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional													$ 2,136,600	[1],[2]	$ 6,221,000	[1],[2]	$ 2,136,600	[1],[2]	$ 6,221,000	[1],[2]
Notional, Forwards and Futures					1,961,000	[1],[2]	2,925,000	[1],[2]	1,961,000	[1],[2]	2,925,000	[1],[2]
Assets													4,859	[1],[2]	39,785	[1],[2]	4,859	[1],[2]	39,785	[1],[2]
Assets, Forwards and Futures					18,712	[1],[2]	5,654	[1],[2]	18,712	[1],[2]	5,654	[1],[2]
Liabilities													18,330	[1],[2]	26,934	[1],[2]	18,330	[1],[2]	26,934	[1],[2]
Liabilities, Forwards and Futures					1,091	[1],[2]	6,311	[1],[2]	1,091	[1],[2]	6,311	[1],[2]
Gains/(Losses)													(3,466)	[1],[2]	14,885	[1],[2]	918	[1],[2]	22,224	[1],[2]
Gains/(Losses), Forwards and Futures					10,943	[1],[2]	10,391	[1],[2]	9,632	[1],[2]	6,348	[1],[2]
Total MSR recognized by FHN	129,291	144,069	186,958	207,319																	126,164	[2],[3]	183,364	[2],[3]	126,164	[2],[3]	183,364	[2],[3]
Fair value of retained interests	1,361,717	988,217	1,196,380																										20,567	[2],[4]	31,623	[2],[4]	20,567	[2],[4]	31,623	[2],[4]
Gains/(Losses)																					$ (4,131)	[2],[3]	$ (10,457)	[2],[3]	$ 900	[2],[3]	$ (3,325)	[2],[3]	$ (1,513)	[2],[4]	$ 597	[2],[4]	$ (553)	[2],[4]	$ 2,641	[2],[4]

[1] Assets included in the Other assets section of the Consolidated Condensed Statements of Condition. Liabilities included in the Other liabilities section of the Consolidated Condensed Statements of Condition.

[2] Gains/losses included in the Mortgage banking income section of the Consolidated Condensed Statements of Income.

[3] Assets included in the Mortgage servicing rights section of the Consolidated Condensed Statements of Condition.

[4] Assets included in the Trading securities section of the Consolidated Condensed Statements of Condition.