Variable Interest Entities (Summary Of VIE Not Consolidated By FHN) (Details) (USD $)	Mar. 31, 2014		Dec. 31, 2013	Mar. 31, 2013		Dec. 31, 2012
Variable Interest Entity [Line Items]
Loans, net of unearned income	$ 15,119,461,000		$ 15,389,074,000	$ 15,889,670,000
Term borrowings	1,507,048,000		1,739,859,000	2,197,864,000
Trading securities	1,194,749,000		801,718,000	1,397,746,000
Total MSR recognized by FHN	4,687,000		72,793,000	109,102,000		114,311,000
Custodial balances	4,534,245,000		4,637,839,000	4,454,045,000
Securities available-for-sale	3,571,179,000	[1]	3,398,457,000	3,190,219,000	[2]
Low Income Housing Partnerships [Member]
Variable Interest Entity [Line Items]
Maximum Loss Exposure	48,067,000	[3],[4]		52,528,000	[3],[5]
Maximum loss exposure, contractual funding commitments	6,300,000			1,900,000
Liability Recognized	0	[3],[4]		0	[3],[5]
Low Income Housing Partnerships [Member] | Other Assets Member
Variable Interest Entity [Line Items]
Maximum loss exposure, current investments	41,700,000			50,600,000
New Market Tax Credit Llcs [Member]
Variable Interest Entity [Line Items]
Maximum Loss Exposure	22,492,000	[3],[6]		23,494,000	[3],[7]
Liability Recognized	0	[3],[6]		0	[3],[7]
New Market Tax Credit Llcs [Member] | Current Investment Funded By Borrowings [Member]
Variable Interest Entity [Line Items]
Maximum loss exposure, current investments	18,000,000			18,000,000
Small Issuer Trust Preferred Holdings [Member]
Variable Interest Entity [Line Items]
Maximum Loss Exposure	375,247,000	[8]		418,404,000	[8]
Liability Recognized	0	[8]		0	[8]
On Balance Sheet Trust Preferred Securitization [Member]
Variable Interest Entity [Line Items]
Maximum Loss Exposure	53,463,000	[9]		54,577,000	[10]
Liability Recognized	60,711,000	[9]		59,597,000	[10]
Loans, net of unearned income	112,500,000			112,500,000
Term borrowings	60,700,000			59,600,000
Trading securities	1,700,000			1,700,000
Proprietary Trust Preferred Issuances [Member]
Variable Interest Entity [Line Items]
Liability Recognized	206,186,000	[11]		206,186,000	[11]
Proprietary Agency Residential Mortgage Securitizations [Member]
Variable Interest Entity [Line Items]
Maximum Loss Exposure	54,559,000	[12]		416,648,000	[13]
Liability Recognized	0	[12]		0	[13]
Proprietary Agency Residential Mortgage Securitizations [Member] | Other Assets Member
Variable Interest Entity [Line Items]
Aggregate servicing advances	45,500,000			304,800,000
On Balance Sheet Consumer Loan Securitizations [Member]
Variable Interest Entity [Line Items]
Maximum Loss Exposure				14,477,000	[14]
Liability Recognized				270,385,000	[14]
Loans, net of unearned income				284,900,000
Term borrowings				270,400,000
Holdings Of Agency Mortgage Backed Securities [Member]
Variable Interest Entity [Line Items]
Maximum Loss Exposure	3,861,630,000	[15],[8]		3,584,187,000	[16],[8]
Liability Recognized	0	[15],[8]		0	[16],[8]
Trading securities	537,300,000			669,300,000
Securities available-for-sale	3,300,000,000			2,900,000,000
Short Positions In Agency Mortgage Backed Securities [Member]
Variable Interest Entity [Line Items]
Liability Recognized	1,586,000	[11]		51,108,000	[11]
Commercial Loan Troubled Debt Restructurings [Member]
Variable Interest Entity [Line Items]
Maximum Loss Exposure	58,736,000	[17],[18]		68,921,000	[17],[19]
Maximum loss exposure, contractual funding commitments	1,500,000			3,200,000
Liability Recognized	0	[17],[18]		0	[17],[19]
Loans, net of unearned income	57,200,000			65,700,000
Managed Discretionary Trusts [Member]
Variable Interest Entity [Line Items]
Maximum Loss Exposure	0	[11]		0	[11]
Liability Recognized	0	[11]		0	[11]
Proprietary Residential Mortgage Securitizations [Member]
Variable Interest Entity [Line Items]
Trading securities	6,600,000			7,600,000
Total MSR recognized by FHN	1,400,000			66,600,000
Agency Residential Mortgage Securitizations [Member]
Variable Interest Entity [Line Items]
Trading securities				8,800,000
Total MSR recognized by FHN	$ 1,000,000			$ 28,700,000

[1] Includes $3.3 billion of securities pledged to secure public deposits, securities sold under agreements to repurchase, and for other purposes.

[2] Includes $2.9 billion of securities pledged to secure public deposits, securities sold under agreements to repurchase, and for other purposes.

[3] A liability is not recognized as investments are written down over the life of the related tax credit.

[4] Maximum loss exposure represents $41.7 million of current investments and $6.3 million of contractual funding commitments. Only the current investment amount is included in Other assets.

[5] Maximum loss exposure represents $50.6 million of current investments and $1.9 million of contractual funding commitments. Only the current investment amount is included in Other assets.

[6] Maximum loss exposure represents current investment balance. Of the initial investment, $18.0 million was funded through loans from community development enterprises.

[7] Maximum loss exposure represents current investment balance. Of the initial investment $18.0 million was funded through loans from community development enterprises.

[8] Maximum loss exposure represents the value of current investments. A liability is not recognized as FHN is solely a holder of the trusts’ securities.

[9] Includes $112.5 million classified as Loans, net of unearned income, and $1.7 million classified as Trading securities which are offset by $60.7 million classified as Term borrowings.

[10] Includes $112.5 million classified as Loans, net of unearned income, and $1.7 million classified as Trading securities which are offset by $59.6 million classified as Term borrowings.

[11] No exposure to loss due to the nature of FHN’s involvement.

[12] Includes $1.4 million and $1.0 million classified as MSR related to proprietary and agency residential mortgage securitizations, respectively, and $6.6 million classified as Trading securities related to proprietary residential mortgage securitizations. Aggregate servicing advances of $45.5 million are classified as Other assets.

[13] Includes $66.6 million and $28.7 million classified as MSR and $7.6 million and $8.8 million classified as Trading securities related to proprietary and agency residential mortgage securitizations, respectively. Aggregate servicing advances of $304.8 million are classified as Other assets.

[14] Includes $284.9 million classified as Loans, net of unearned income which are offset by $270.4 million classified as Term borrowings.

[15] Includes $537.3 million classified as Trading securities and $3.3 billion classified as Securities available-for-sale.

[16] Includes $669.3 million classified as Trading securities and $2.9 billion classified as Securities available-for-sale.

[17] A liability is not recognized as the loans are the only variable interests held in the troubled commercial borrowers’ operations.

[18] Maximum loss exposure represents $57.2 million of current receivables and $1.5 million of contractual funding commitments on loans related to commercial borrowers involved in a troubled debt restructuring.

[19] Maximum loss exposure represents $65.7 million of current receivables and $3.2 million of contractual funding commitments on loans related to commercial borrowers involved in a troubled debt restructuring.