Fair Value Of Assets And Liabilities (Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013	Mar. 31, 2013		Dec. 31, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	$ 1,194,749		$ 801,718	$ 1,397,746
Loans held-for-sale	229,219			232,684
Securities available-for-sale	3,571,179	[1]	3,398,457	3,190,219	[2]
Total MSR recognized by FHN	4,687		72,793	109,102		114,311
Total other assets	189,800			297,117
Total assets	5,030,896			5,029,374
Other short-term borrowings				10,984
Total other liabilities	137,863			199,999
Total liabilities	805,120			992,289
Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	0			0
Securities available-for-sale	26,482			14,996
Total MSR recognized by FHN	0			0
Total other assets	27,350			38,578
Total assets	53,832			53,574
Other short-term borrowings				0
Total other liabilities	2,738			16,580
Total liabilities	2,738			16,580
Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	0			0
Securities available-for-sale	3,377,977			2,968,653
Total MSR recognized by FHN	0			0
Total other assets	162,450			258,539
Total assets	4,728,583			4,608,479
Other short-term borrowings				0
Total other liabilities	130,180			181,369
Total liabilities	797,437			962,675
Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	229,219			232,684
Securities available-for-sale	7,982			9,076
Total MSR recognized by FHN	4,687			109,102
Total other assets	0			0
Total assets	248,481			367,321
Other short-term borrowings				10,984
Total other liabilities	4,945			2,050
Total liabilities	4,945			13,034
Fair Value Measurements Recurring Member
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	3,412,441			2,992,725
U S Treasury Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	39,990			39,994
U S Treasury Securities [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
U S Treasury Securities [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	39,990			39,994
U S Treasury Securities [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
Government Agency Issued Mortgage-Backed Securities ("MBS") [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	792,562			1,065,551
Government Agency Issued Mortgage-Backed Securities ("MBS") [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
Government Agency Issued Mortgage-Backed Securities ("MBS") [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	792,562			1,065,551
Government Agency Issued Mortgage-Backed Securities ("MBS") [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	2,531,770			1,849,353
Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	2,531,770			1,849,353
Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
Other U.S. Government Agencies [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	2,182			3,276
Other U.S. Government Agencies [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
Other U.S. Government Agencies [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
Other U.S. Government Agencies [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	2,182			3,276
States And Municipalities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	15,155			15,255
States And Municipalities [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
States And Municipalities [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	13,655			13,755
States And Municipalities [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	1,500			1,500
Venture Capital Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	4,300			4,300
Venture Capital Investments [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
Venture Capital Investments [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
Venture Capital Investments [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	4,300			4,300
Equity Mutual Funds And Other [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	26,482			14,996
Equity Mutual Funds And Other [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	26,482			14,996
Equity Mutual Funds And Other [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
Equity Mutual Funds And Other [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available-for-sale	0			0
Deferred Compensation Assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	23,335			22,785
Deferred Compensation Assets [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	23,335			22,785
Deferred Compensation Assets [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Deferred Compensation Assets [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Derivatives Forwards And Futures [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	4,015			15,793
Total other liabilities	2,738			16,580
Derivatives Forwards And Futures [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	4,015			15,793
Total other liabilities	2,738			16,580
Derivatives Forwards And Futures [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Total other liabilities	0			0
Derivatives Forwards And Futures [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Total other liabilities	0			0
Derivatives, Interest Rate Contracts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	162,450			258,539
Total other liabilities	130,180			181,364
Derivatives, Interest Rate Contracts [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Total other liabilities	0			0
Derivatives, Interest Rate Contracts [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	162,450			258,539
Total other liabilities	130,180			181,364
Derivatives, Interest Rate Contracts [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Total other liabilities	0			0
Derivatives Other [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other liabilities	4,945			2,055
Derivatives Other [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other liabilities	0			0
Derivatives Other [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other liabilities	0			5
Derivatives Other [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other liabilities	4,945			2,050
Capital Markets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	1,188,161			1,381,292
Total trading liabilities - capital markets	667,257			781,306
Capital Markets [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	1,188,156			1,381,287
Total trading liabilities - capital markets	667,257			781,306
Capital Markets [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	5			5
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | U S Treasury Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	145,136			99,618
Total trading liabilities - capital markets	420,574			434,119
Capital Markets [Member] | U S Treasury Securities [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | U S Treasury Securities [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	145,136			99,618
Total trading liabilities - capital markets	420,574			434,119
Capital Markets [Member] | U S Treasury Securities [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | Government Agency Issued Mortgage-Backed Securities ("MBS") [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	412,994			385,351
Total trading liabilities - capital markets	1,083			26,121
Capital Markets [Member] | Government Agency Issued Mortgage-Backed Securities ("MBS") [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | Government Agency Issued Mortgage-Backed Securities ("MBS") [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	412,994			385,351
Total trading liabilities - capital markets	1,083			26,121
Capital Markets [Member] | Government Agency Issued Mortgage-Backed Securities ("MBS") [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	124,304			283,932
Total trading liabilities - capital markets	503			24,986
Capital Markets [Member] | Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	124,304			283,932
Total trading liabilities - capital markets	503			24,986
Capital Markets [Member] | Government Agency Issued Collateralized Mortgage Obligations ("CMO") [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | Other U.S. Government Agencies [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	86,672			195,051
Total trading liabilities - capital markets	9,739			50,547
Capital Markets [Member] | Other U.S. Government Agencies [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | Other U.S. Government Agencies [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	86,672			195,051
Total trading liabilities - capital markets	9,739			50,547
Capital Markets [Member] | Other U.S. Government Agencies [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | States And Municipalities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	29,787			21,141
Total trading liabilities - capital markets	1,436
Capital Markets [Member] | States And Municipalities [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0
Capital Markets [Member] | States And Municipalities [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	29,787			21,141
Total trading liabilities - capital markets	1,436
Capital Markets [Member] | States And Municipalities [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0
Capital Markets [Member] | Corporate And Other Debt [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	382,346			396,191
Total trading liabilities - capital markets	233,287			245,533
Capital Markets [Member] | Corporate And Other Debt [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | Corporate And Other Debt [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	382,341			396,186
Total trading liabilities - capital markets	233,287			245,533
Capital Markets [Member] | Corporate And Other Debt [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	5			5
Total trading liabilities - capital markets	0			0
Capital Markets [Member] | Equity Mutual Funds And Other [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	6,922			8
Total trading liabilities - capital markets	635
Capital Markets [Member] | Equity Mutual Funds And Other [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0
Capital Markets [Member] | Equity Mutual Funds And Other [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	6,922			8
Total trading liabilities - capital markets	635
Capital Markets [Member] | Equity Mutual Funds And Other [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - capital markets	0
Mortgage Banking [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	6,588			16,454
Mortgage Banking [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	6,588			16,454
Mortgage Banking [Member] | Principal Only Strip [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	4,764			5,293
Mortgage Banking [Member] | Principal Only Strip [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking [Member] | Principal Only Strip [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking [Member] | Principal Only Strip [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	4,764			5,293
Mortgage Banking [Member] | Interest Only Strip [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	339			11,161
Mortgage Banking [Member] | Interest Only Strip [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking [Member] | Interest Only Strip [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking [Member] | Interest Only Strip [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	339			11,161
Mortgage Banking [Member] | Subordinated Bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	1,485
Mortgage Banking [Member] | Subordinated Bonds [Member] | Fair Value Inputs Level1 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0
Mortgage Banking [Member] | Subordinated Bonds [Member] | Fair Value Inputs Level2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0
Mortgage Banking [Member] | Subordinated Bonds [Member] | Fair Value Inputs Level3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	$ 1,485

[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.