Derivatives (Derivatives associated with legacy Mortgage Servicing Activities) (Details) (USD $) In Thousands, unless otherwise specified					3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2013 Forwards And Futures [Member] Retained Interest [Member] Hedging Instruments [Member]	Mar. 31, 2012 Forwards And Futures [Member] Retained Interest [Member] Hedging Instruments [Member]	Mar. 31, 2013 Interest Rate Swaps And Swaptions [Member] Retained Interest [Member] Hedging Instruments [Member]	Mar. 31, 2012 Interest Rate Swaps And Swaptions [Member] Retained Interest [Member] Hedging Instruments [Member]	Mar. 31, 2013 Mortgage Servicing Rights [Member] Retained Interest [Member] Hedged Items [Member]	Mar. 31, 2012 Mortgage Servicing Rights [Member] Retained Interest [Member] Hedged Items [Member]	Mar. 31, 2013 Other Retained Interests [Member] Retained Interest [Member] Hedged Items [Member]	Mar. 31, 2012 Other Retained Interests [Member] Retained Interest [Member] Hedged Items [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional							$ 735,000	$ 2,420,000
Notional, Forwards and Futures					124,000	2,361,000
Assets							1,956	9,713
Assets, Forwards and Futures					162	25,200
Liabilities							215	30,443
Liabilities, Forwards and Futures					0	1,155
Gains/(Losses)							735	4,384
Gains/(Losses), Forwards and Futures					(411)	(1,311)
Total MSR recognized by FHN	109,102	114,311	142,956	144,069					106,329	139,672
Fair value of retained interests	1,397,746	1,262,720	1,238,041								16,454	24,610
Gains/(Losses)									$ 1,177	$ 5,031	$ 481	$ 960