Loans (Period-End Balances And Various Asset Quality Attributes By Origination Vintage For Permanent Mortgage Classes Of Loans) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013		Dec. 31, 2012	Mar. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 15,889,670		$ 16,708,582	$ 15,971,330
Permanent Mortgage Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Permanent Mortgage - Period End Balance	793,282			788,700
Avg orig FICO	731			734
Avg Refreshed FICO	711			711
Loans, net of unearned income	793,282			788,700
Permanent Mortgage Portfolio Segment [Member] | Origination Vintage Period Pre2004 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Permanent Mortgage - Period End Balance	249,523	[1]		146,858
Avg orig FICO	726			724
Avg Refreshed FICO	727			732
Permanent Mortgage Portfolio Segment [Member] | Origination Vintage Period 2004 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Permanent Mortgage - Period End Balance	28,662			49,152
Avg orig FICO	714			719
Avg Refreshed FICO	691			688
Permanent Mortgage Portfolio Segment [Member] | Origination Vintage Period 2005 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Permanent Mortgage - Period End Balance	47,382			58,748
Avg orig FICO	739			740
Avg Refreshed FICO	713			715
Permanent Mortgage Portfolio Segment [Member] | Origination Vintage Period 2006 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Permanent Mortgage - Period End Balance	89,179			104,922
Avg orig FICO	732			735
Avg Refreshed FICO	712			708
Permanent Mortgage Portfolio Segment [Member] | Origination Vintage Period 2007 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Permanent Mortgage - Period End Balance	260,136			288,517
Avg orig FICO	734			734
Avg Refreshed FICO	711			704
Permanent Mortgage Portfolio Segment [Member] | Origination Vintage Period 2008 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Permanent Mortgage - Period End Balance	118,400			140,503
Avg orig FICO	742			742
Avg Refreshed FICO	712			713
Restricted Permanent Mortgage Real Estate Loans And Secured Borrowings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 13,000		$ 13,200	$ 38,000

[1] Increase in 2013 balance within the pre-2004 vintages reflect the impact of clean-up calls exercised by FHN during first quarter 2013 and third quarter 2012.