OTHER REAL ESTATE OWNED (Details) (USD $)	3 Months Ended				12 Months Ended
	Mar. 31, 2013		Mar. 31, 2012		Dec. 31, 2012
Activity in other real estate owned [Roll Forward]
Balance at beginning of year	$ 103,248,000	[1]	$ 173,805,000		$ 173,805,000
Additions to foreclosed properties [Abstract]
New foreclosed properties	2,222,000		10,766,000		32,389,000
Reductions in foreclosed properties [Abstract]
Sales	(7,811,000)		(11,771,000)		(81,220,000)
Writedowns	(1,345,000)		(4,992,000)		(21,726,000)
Balance at end of year	96,314,000		167,808,000		103,248,000	[1]
Other real estate owned by geographical location, segment and class [Abstract]
Total	96,314,000		167,808,000		103,248,000	[1]
Foreclosed property expenses [Abstract]
Total foreclosed property expenses	2,354,000		8,409,000
Realized net losses on dispositions and holding losses on valuations of foreclosed properties	1,100,000		5,800,000
Alabama and Florida Panhandle [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	16,390,000		26,339,000		17,254,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	16,390,000		26,339,000		17,254,000
Arkansas [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	3,423,000	[2]	4,906,000	[2]	3,185,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	3,423,000	[2]	4,906,000	[2]	3,185,000	[2]
Mississippi [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	18,490,000	[2]	36,046,000	[2]	19,916,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	18,490,000	[2]	36,046,000	[2]	19,916,000	[2]
Missouri [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	525,000		4,502,000		1,089,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	525,000		4,502,000		1,089,000
Greater Memphis Area [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	42,020,000		62,875,000		41,950,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	42,020,000		62,875,000		41,950,000
Tennessee [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	11,826,000	[2]	25,657,000	[2]	12,482,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	11,826,000	[2]	25,657,000	[2]	12,482,000	[2]
Texas and Louisiana [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	3,046,000		3,203,000		3,227,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	3,046,000		3,203,000		3,227,000
Other Geographical Areas [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	594,000		4,280,000		4,145,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	594,000		4,280,000		4,145,000
Commercial and industrial segment [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	241,000		1,260,000		501,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	241,000		1,260,000		501,000
Commercial and industrial segment [Member] | Alabama and Florida Panhandle [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	241,000		423,000		395,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	241,000		423,000		395,000
Commercial and industrial segment [Member] | Arkansas [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0	[2]	16,000	[2]	0	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	0	[2]	16,000	[2]	0	[2]
Commercial and industrial segment [Member] | Mississippi [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0	[2]	0	[2]	106,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	0	[2]	0	[2]	106,000	[2]
Commercial and industrial segment [Member] | Missouri [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		0		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		0		0
Commercial and industrial segment [Member] | Greater Memphis Area [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		821,000		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		821,000		0
Commercial and industrial segment [Member] | Tennessee [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0	[2]	0	[2]	0	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	0	[2]	0	[2]	0	[2]
Commercial and industrial segment [Member] | Texas and Louisiana [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		0		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		0		0
Commercial and industrial segment [Member] | Other Geographical Areas [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		0		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		0		0
Real estate segment [Member] | Consumer mortgages [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	6,598,000		18,814,000		10,117,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	6,598,000		18,814,000		10,117,000
Real estate segment [Member] | Home equity [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	44,000		775,000		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	44,000		775,000		0
Real estate segment [Member] | Agricultural [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	4,354,000		5,167,000		4,425,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	4,354,000		5,167,000		4,425,000
Real estate segment [Member] | Commercial and industrial-owner occupied [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	4,250,000		9,374,000		4,745,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	4,250,000		9,374,000		4,745,000
Real estate segment [Member] | Construction, acquisition and development [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	76,739,000		113,515,000		78,977,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	76,739,000		113,515,000		78,977,000
Real estate segment [Member] | Commercial Real Estate [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	2,881,000		16,979,000		3,235,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	2,881,000		16,979,000		3,235,000
Real estate segment [Member] | Alabama and Florida Panhandle [Member] | Consumer mortgages [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	1,114,000		3,505,000		1,714,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	1,114,000		3,505,000		1,714,000
Real estate segment [Member] | Alabama and Florida Panhandle [Member] | Home equity [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		0		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		0		0
Real estate segment [Member] | Alabama and Florida Panhandle [Member] | Agricultural [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	870,000		902,000		856,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	870,000		902,000		856,000
Real estate segment [Member] | Alabama and Florida Panhandle [Member] | Commercial and industrial-owner occupied [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	157,000		1,564,000		155,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	157,000		1,564,000		155,000
Real estate segment [Member] | Alabama and Florida Panhandle [Member] | Construction, acquisition and development [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	13,605,000		16,179,000		13,610,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	13,605,000		16,179,000		13,610,000
Real estate segment [Member] | Alabama and Florida Panhandle [Member] | Commercial Real Estate [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	356,000		3,557,000		478,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	356,000		3,557,000		478,000
Real estate segment [Member] | Arkansas [Member] | Consumer mortgages [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	734,000	[2]	615,000	[2]	173,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	734,000	[2]	615,000	[2]	173,000	[2]
Real estate segment [Member] | Arkansas [Member] | Home equity [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0	[2]	26,000	[2]	0	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	0	[2]	26,000	[2]	0	[2]
Real estate segment [Member] | Arkansas [Member] | Agricultural [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0	[2]	0	[2]	0	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	0	[2]	0	[2]	0	[2]
Real estate segment [Member] | Arkansas [Member] | Commercial and industrial-owner occupied [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	101,000	[2]	656,000	[2]	146,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	101,000	[2]	656,000	[2]	146,000	[2]
Real estate segment [Member] | Arkansas [Member] | Construction, acquisition and development [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	1,167,000	[2]	1,766,000	[2]	1,430,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	1,167,000	[2]	1,766,000	[2]	1,430,000	[2]
Real estate segment [Member] | Arkansas [Member] | Commercial Real Estate [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	1,410,000	[2]	1,744,000	[2]	1,420,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	1,410,000	[2]	1,744,000	[2]	1,420,000	[2]
Real estate segment [Member] | Mississippi [Member] | Consumer mortgages [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	2,653,000	[2]	2,970,000	[2]	2,220,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	2,653,000	[2]	2,970,000	[2]	2,220,000	[2]
Real estate segment [Member] | Mississippi [Member] | Home equity [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	44,000	[2]	22,000	[2]	0	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	44,000	[2]	22,000	[2]	0	[2]
Real estate segment [Member] | Mississippi [Member] | Agricultural [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0	[2]	730,000	[2]	99,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	0	[2]	730,000	[2]	99,000	[2]
Real estate segment [Member] | Mississippi [Member] | Commercial and industrial-owner occupied [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	1,139,000	[2]	2,583,000	[2]	1,602,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	1,139,000	[2]	2,583,000	[2]	1,602,000	[2]
Real estate segment [Member] | Mississippi [Member] | Construction, acquisition and development [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	14,586,000	[2]	25,510,000	[2]	15,659,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	14,586,000	[2]	25,510,000	[2]	15,659,000	[2]
Real estate segment [Member] | Mississippi [Member] | Commercial Real Estate [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	4,000	[2]	3,241,000	[2]	3,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	4,000	[2]	3,241,000	[2]	3,000	[2]
Real estate segment [Member] | Missouri [Member] | Consumer mortgages [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		0		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		0		0
Real estate segment [Member] | Missouri [Member] | Home equity [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		0		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		0		0
Real estate segment [Member] | Missouri [Member] | Agricultural [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		0		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		0		0
Real estate segment [Member] | Missouri [Member] | Commercial and industrial-owner occupied [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		2,113,000		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		2,113,000		0
Real estate segment [Member] | Missouri [Member] | Construction, acquisition and development [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	431,000		1,965,000		734,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	431,000		1,965,000		734,000
Real estate segment [Member] | Missouri [Member] | Commercial Real Estate [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		307,000		263,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		307,000		263,000
Real estate segment [Member] | Greater Memphis Area [Member] | Consumer mortgages [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	756,000		4,713,000		961,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	756,000		4,713,000		961,000
Real estate segment [Member] | Greater Memphis Area [Member] | Home equity [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		586,000		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		586,000		0
Real estate segment [Member] | Greater Memphis Area [Member] | Agricultural [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	1,106,000		1,164,000		1,089,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	1,106,000		1,164,000		1,089,000
Real estate segment [Member] | Greater Memphis Area [Member] | Commercial and industrial-owner occupied [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	2,638,000		1,829,000		2,630,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	2,638,000		1,829,000		2,630,000
Real estate segment [Member] | Greater Memphis Area [Member] | Construction, acquisition and development [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	35,939,000		46,007,000		35,717,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	35,939,000		46,007,000		35,717,000
Real estate segment [Member] | Greater Memphis Area [Member] | Commercial Real Estate [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	833,000		7,318,000		819,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	833,000		7,318,000		819,000
Real estate segment [Member] | Tennessee [Member] | Consumer mortgages [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	716,000	[2]	3,523,000	[2]	624,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	716,000	[2]	3,523,000	[2]	624,000	[2]
Real estate segment [Member] | Tennessee [Member] | Home equity [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0	[2]	141,000	[2]	0	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	0	[2]	141,000	[2]	0	[2]
Real estate segment [Member] | Tennessee [Member] | Agricultural [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	2,204,000	[2]	2,371,000	[2]	2,169,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	2,204,000	[2]	2,371,000	[2]	2,169,000	[2]
Real estate segment [Member] | Tennessee [Member] | Commercial and industrial-owner occupied [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	67,000	[2]	164,000	[2]	66,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	67,000	[2]	164,000	[2]	66,000	[2]
Real estate segment [Member] | Tennessee [Member] | Construction, acquisition and development [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	8,682,000	[2]	19,458,000	[2]	9,535,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	8,682,000	[2]	19,458,000	[2]	9,535,000	[2]
Real estate segment [Member] | Tennessee [Member] | Commercial Real Estate [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	144,000	[2]	0	[2]	76,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	144,000	[2]	0	[2]	76,000	[2]
Real estate segment [Member] | Texas and Louisiana [Member] | Consumer mortgages [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	625,000		111,000		760,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	625,000		111,000		760,000
Real estate segment [Member] | Texas and Louisiana [Member] | Home equity [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		0		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		0		0
Real estate segment [Member] | Texas and Louisiana [Member] | Agricultural [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	174,000		0		212,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	174,000		0		212,000
Real estate segment [Member] | Texas and Louisiana [Member] | Commercial and industrial-owner occupied [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	148,000		174,000		146,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	148,000		174,000		146,000
Real estate segment [Member] | Texas and Louisiana [Member] | Construction, acquisition and development [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	1,874,000		2,630,000		1,844,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	1,874,000		2,630,000		1,844,000
Real estate segment [Member] | Texas and Louisiana [Member] | Commercial Real Estate [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	134,000		233,000		176,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	134,000		233,000		176,000
Real estate segment [Member] | Other Geographical Areas [Member] | Consumer mortgages [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		3,377,000		3,665,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		3,377,000		3,665,000
Real estate segment [Member] | Other Geographical Areas [Member] | Home equity [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		0		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		0		0
Real estate segment [Member] | Other Geographical Areas [Member] | Agricultural [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		0		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		0		0
Real estate segment [Member] | Other Geographical Areas [Member] | Commercial and industrial-owner occupied [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		291,000		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		291,000		0
Real estate segment [Member] | Other Geographical Areas [Member] | Construction, acquisition and development [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	455,000		0		448,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	455,000		0		448,000
Real estate segment [Member] | Other Geographical Areas [Member] | Commercial Real Estate [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	0		579,000		0
Other real estate owned by geographical location, segment and class [Abstract]
Total	0		579,000		0
All other [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	1,207,000		1,924,000		1,248,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	1,207,000		1,924,000		1,248,000
All other [Member] | Alabama and Florida Panhandle [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	47,000		209,000		46,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	47,000		209,000		46,000
All other [Member] | Arkansas [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	11,000	[2]	83,000	[2]	16,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	11,000	[2]	83,000	[2]	16,000	[2]
All other [Member] | Mississippi [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	64,000	[2]	990,000	[2]	227,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	64,000	[2]	990,000	[2]	227,000	[2]
All other [Member] | Missouri [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	94,000		117,000		92,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	94,000		117,000		92,000
All other [Member] | Greater Memphis Area [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	748,000		437,000		734,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	748,000		437,000		734,000
All other [Member] | Tennessee [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	13,000	[2]	0	[2]	12,000	[2]
Other real estate owned by geographical location, segment and class [Abstract]
Total	13,000	[2]	0	[2]	12,000	[2]
All other [Member] | Texas and Louisiana [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	91,000		55,000		89,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	91,000		55,000		89,000
All other [Member] | Other Geographical Areas [Member]
Reductions in foreclosed properties [Abstract]
Balance at end of year	139,000		33,000		32,000
Other real estate owned by geographical location, segment and class [Abstract]
Total	$ 139,000		$ 33,000		$ 32,000

[1] Derived from audited financial statements.

[2] Excludes the Greater Memphis Area.