Business Segment Information (Amounts Of Consolidated Revenue, Expense, Tax And Assets) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013 number		Mar. 31, 2012
Segment Reporting Information [Line Items]
Net interest income	$ 161,382		$ 171,929
Provision/(provision credit) for loan losses	15,000		8,000
Noninterest income	156,427		202,441
Noninterest expense	240,540		321,994
Income/(loss) before income taxes	62,269		44,376
Provision/(benefit) for income taxes	17,730		10,570
Income/(loss) from continuing operations	44,539		33,806
Income/(loss) from discontinued operations, net of tax	430	[1]	(435)	[1]
Net income/(loss)	44,969		33,371
Average assets	25,078,227		25,200,373
Number of Operating Segments	4
Regional Banking [Member]
Segment Reporting Information [Line Items]
Net interest income	145,097		146,636
Provision/(provision credit) for loan losses	(2,485)		(7,426)
Noninterest income	59,144		60,052
Noninterest expense	128,713		140,643
Income/(loss) before income taxes	78,013		73,471
Provision/(benefit) for income taxes	28,352		26,752
Net income/(loss)	49,661		46,719
Average assets	12,956,515		12,231,651
Capital Markets [Member]
Segment Reporting Information [Line Items]
Net interest income	3,847		5,680
Noninterest income	76,612		106,775
Noninterest expense	61,668		80,306
Income/(loss) before income taxes	18,791		32,149
Provision/(benefit) for income taxes	7,123		12,238
Net income/(loss)	11,668		19,911
Average assets	2,492,129		2,351,599
Corporate [Member]
Segment Reporting Information [Line Items]
Net interest income	(7,717)		(5,309)
Noninterest income	7,855		9,262
Noninterest expense	17,587		22,373
Income/(loss) before income taxes	(17,449)		(18,420)
Provision/(benefit) for income taxes	(11,171)		(11,934)
Net income/(loss)	(6,278)		(6,486)
Average assets	5,254,397		5,427,352
Non Strategic [Member]
Segment Reporting Information [Line Items]
Net interest income	20,155		24,922
Provision/(provision credit) for loan losses	17,485		15,426
Noninterest income	12,816		26,352
Noninterest expense	32,572		78,672
Income/(loss) before income taxes	(17,086)		(42,824)
Provision/(benefit) for income taxes	(6,574)		(16,486)
Income/(loss) from continuing operations	(10,512)		(26,338)
Income/(loss) from discontinued operations, net of tax	430		(435)
Net income/(loss)	(10,082)		(26,773)
Average assets	$ 4,375,186		$ 5,189,771

[1] Due to the nature of the preferred stock issued by FHN and its subsidiaries, all components of Income/(loss) from discontinued operations, net of tax have been attributed solely to FHN as the controlling interest holder.