Derivatives (Narrative) (Details) (USD $)	3 Months Ended	6 Months Ended										6 Months Ended	3 Months Ended	12 Months Ended				3 Months Ended						3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Jun. 30, 2010	Jun. 30, 2011 Interest Rate Swaps [Member]	Jun. 30, 2010 Interest Rate Swaps [Member]	Jun. 30, 2011 FHN [Member] Fixed Interest Rate Swaps to Hedge [Member]	Jun. 30, 2010 FHN [Member] Fixed Interest Rate Swaps to Hedge [Member]	Jun. 30, 2011 FHN [Member] Fixed Interest Rate Swaps to Hedge [Member] Long Term Debt Hedged With Fair Value Interest Rate Derivatives Using Shortcut Method [Member]	Jun. 30, 2010 FHN [Member] Fixed Interest Rate Swaps to Hedge [Member] Long Term Debt Hedged With Fair Value Interest Rate Derivatives Using Shortcut Method [Member]	Jun. 30, 2011 FHN [Member] Fixed Interest Rate Swaps to Hedge [Member] Long Term Debt Hedged With Fair Value Interest Rate Derivatives Using Long Haul Method [Member]	Jun. 30, 2011 FHN [Member] Visa Derivative [Member]	Dec. 31, 2010 FHN [Member] Visa Derivative [Member]	Dec. 31, 2010 FHN [Member] Visa Derivative [Member] Class B Shares [Member]	Jun. 30, 2011 FHN [Member] Additional Derivative Agreements [Member] Derivative Instruments with Adjustable Collateral Posting Thresholds [Member]	Jun. 30, 2010 FHN [Member] Additional Derivative Agreements [Member] Derivative Instruments with Adjustable Collateral Posting Thresholds [Member]	Jun. 30, 2011 FHN [Member] Visa Interest [Member]	Dec. 31, 2010 FHN [Member] Visa Interest [Member] Class B Shares [Member]	Jun. 30, 2011 FHN [Member] Derivative Instruments With Accelerated Termination Provisions [Member]	Jun. 30, 2010 FHN [Member] Derivative Instruments With Accelerated Termination Provisions [Member]	Jun. 30, 2011 FHN [Member] Subordinated Debentures Subject To Mandatory Redemption - Amounts Redeemed [Member]	Jun. 30, 2010 FHN [Member] Subordinated Debentures Subject To Mandatory Redemption - Amounts Redeemed [Member]	Jun. 30, 2011 FHN [Member]	Jun. 30, 2010 FHN [Member]	Jun. 30, 2011 FHN [Member]	Jun. 30, 2010 FHN [Member]
Collateral cash receivables	$ 163,000,000	$ 163,000,000			$ 168,500,000
Collateral cash payables	124,400,000	124,400,000			120,300,000											124,400,000	120,300,000			118,900,000
Collateral received from counterparties																											0
Securities posted collateral																161,800,000	165,800,000			41,400,000	24,700,000
Net fair value of derivative liablities with credit-risk related contingent accelerated termination provisions																				37,000,000	18,800,000
Net fair value of derivative assets with credit-risk related contingent accelerated termination provisions																				126,800,000	26,100,000
Net fair value of derivative assets with adjustable posting thresholds																134,800,000	158,200,000
Net fair value of derivative liabilities with adjustable posting thresholds																154,700,000	173,200,000
Total trading revenues																								71,200,000	91,800,000	154,400,000	197,100,000
Long-term debt										1,000,000,000	1,000,000,000	500,000,000
Net fair value of interest rate derivatives hedging long-term debt using the shortcut method							2,300,000	101,700,000	114,100,000
Noncallable senior debt maturing date												December 2015
Net fair value of interest rate derivatives hedging subordinated debt using long-haul method						12,000,000		11,400,000																13,200,000	20,000,000	13,200,000	20,000,000
Other long-term debt	2,502,517,000	2,502,517,000		3,228,070,000	2,926,675,000																	200,000,000	200,000,000
Hedged held-to-maturity trust preferred loans principal balance																								201,600,000	215,600,000	201,600,000	215,600,000
Fixed rate conversion termination period, years																										5
Estimated conversion ratio	49.00%	49.00%											49.00%	51.00%
Additional amount deposited into escrow account			400,000,000
Visa class B shares sold															440,000
Payment to the counterparty																		700,000
Derivative liability related to sale of Visa shares																		1,300,000	1,000,000
Foreign currency risk and interest rate risk associated with non-u.s dollar denominated loans	$ 1,200,000	$ 1,200,000