LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 10) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011
Allowance for loan losses:
Ending balance: impaired loans individually evaluated for impairment	$ 4,035		$ 3,598
Ending balance: impaired loans collectively evaluated for impairment	12,373		14,354
Ending balance: all other loans collectively evaluated for impairment	69,225		73,650
Financing Receivable, Allowance for Credit Losses	85,633	88,170	91,602	120,227	130,348	137,710
Financing receivables:
Ending balance: impaired loans individually evaluated for impairment	97,337		119,483
Ending balance: impaired loans collectively evaluated for impairment	111,272		119,306
Ending balance: all other loans collectively evaluated for impairment	2,567,101		2,625,825
Ending balance	2,775,710		2,864,614
Commercial, financial and agricultural [Member]
Allowance for loan losses:
Ending balance: impaired loans individually evaluated for impairment	0		75
Ending balance: impaired loans collectively evaluated for impairment	383		601
Ending balance: all other loans collectively evaluated for impairment	13,583		12,896
Financing Receivable, Allowance for Credit Losses	13,966	14,168	13,572	22,015	24,782	27,243
Financing receivables:
Ending balance: impaired loans individually evaluated for impairment	5,479		7,884
Ending balance: impaired loans collectively evaluated for impairment	9,558		11,166
Ending balance: all other loans collectively evaluated for impairment	578,366		591,251
Ending balance	593,403		610,301
Real estate construction and development [Member]
Allowance for loan losses:
Ending balance: impaired loans individually evaluated for impairment	87		121
Ending balance: impaired loans collectively evaluated for impairment	977		1,331
Ending balance: all other loans collectively evaluated for impairment	10,348		12,982
Financing Receivable, Allowance for Credit Losses	11,412	13,003	14,434	21,829	24,518	24,868
Financing receivables:
Ending balance: impaired loans individually evaluated for impairment	36,828		39,155
Ending balance: impaired loans collectively evaluated for impairment	1,508		3,028
Ending balance: all other loans collectively evaluated for impairment	128,933		132,796
Ending balance	167,269		174,979
One-to-four-family residential [Member]
Allowance for loan losses:
Ending balance: impaired loans individually evaluated for impairment	3,666		3,187
Ending balance: impaired loans collectively evaluated for impairment	9,810		10,455
Ending balance: all other loans collectively evaluated for impairment	21,790		25,255
Financing Receivable, Allowance for Credit Losses	35,266	36,660	38,897	43,702	46,670	50,864
Financing receivables:
Ending balance: impaired loans individually evaluated for impairment	13,839		16,843
Ending balance: impaired loans collectively evaluated for impairment	94,224		98,423
Ending balance: all other loans collectively evaluated for impairment	823,923		871,501
Ending balance	931,986		986,767
Multi-family residential [Member]
Allowance for loan losses:
Ending balance: impaired loans individually evaluated for impairment	0		33
Ending balance: impaired loans collectively evaluated for impairment	753		1,105
Ending balance: all other loans collectively evaluated for impairment	3,369		3,114
Financing Receivable, Allowance for Credit Losses	4,122	4,202	4,252	4,816	4,679	4,851
Financing receivables:
Ending balance: impaired loans individually evaluated for impairment	28,840		34,636
Ending balance: impaired loans collectively evaluated for impairment	707		365
Ending balance: all other loans collectively evaluated for impairment	71,804		68,683
Ending balance	101,351		103,684
Commercial real estate [Member]
Allowance for loan losses:
Ending balance: impaired loans individually evaluated for impairment	282		182
Ending balance: impaired loans collectively evaluated for impairment	448		861
Ending balance: all other loans collectively evaluated for impairment	19,843		19,005
Financing Receivable, Allowance for Credit Losses	20,573	19,720	20,048	27,471	29,273	29,448
Financing receivables:
Ending balance: impaired loans individually evaluated for impairment	12,351		20,965
Ending balance: impaired loans collectively evaluated for impairment	5,240		6,296
Ending balance: all other loans collectively evaluated for impairment	945,889		942,419
Ending balance	963,480		969,680
Consumer and Installment [Member]
Allowance for loan losses:
Ending balance: impaired loans individually evaluated for impairment	0		0
Ending balance: impaired loans collectively evaluated for impairment	2		1
Ending balance: all other loans collectively evaluated for impairment	292		398
Financing Receivable, Allowance for Credit Losses	294	417	399	394	426	436
Financing receivables:
Ending balance: impaired loans individually evaluated for impairment	0		0
Ending balance: impaired loans collectively evaluated for impairment	35		28
Ending balance: all other loans collectively evaluated for impairment	18,186		19,175
Ending balance	$ 18,221		$ 19,203