IMPAIRED LOANS AND ALLOWANCE FOR LOAN LOSSES - Loan Portfolio and Related Allowance (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Carrying Value
Individually Evaluated for Impairment	$ 38,535	$ 43,577
Collectively Evaluated for Impairment	1,892,302	1,770,494
Total	1,930,837	1,814,071
Associated Allowance
Individually Evaluated for Impairment	3,136	3,541
Collectively Evaluated for Impairment	15,443	13,466
Total	18,579	17,007
PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	6,562	7,814
Associated Allowance
Individually Evaluated for Impairment	212	64
Construction and Land Development [Member]
Carrying Value
Individually Evaluated for Impairment	2,667	2,710
Collectively Evaluated for Impairment	91,022	82,769
Total	93,689	85,479
Associated Allowance
Individually Evaluated for Impairment	142	159
Collectively Evaluated for Impairment	745	563
Total	887	722
Construction and Land Development [Member] | PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	1,489	1,557
Associated Allowance
Individually Evaluated for Impairment	212	43
Commercial Real Estate [Member]
Carrying Value
Individually Evaluated for Impairment	9,775	11,446
Collectively Evaluated for Impairment	879,203	821,609
Total	888,978	833,055
Associated Allowance
Individually Evaluated for Impairment	417	529
Collectively Evaluated for Impairment	4,861	3,999
Total	5,278	4,528
Commercial Real Estate [Member] | PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	3,350	4,092
Associated Allowance
Individually Evaluated for Impairment	0	3
Residential Real Estate [Member]
Carrying Value
Individually Evaluated for Impairment	25,342	28,702
Collectively Evaluated for Impairment	669,929	657,344
Total	695,271	686,046
Associated Allowance
Individually Evaluated for Impairment	2,483	2,741
Collectively Evaluated for Impairment	7,203	7,043
Total	9,686	9,784
Residential Real Estate [Member] | PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	506	851
Associated Allowance
Individually Evaluated for Impairment	0	18
Commercial And Financial [Member]
Carrying Value
Individually Evaluated for Impairment	115	120
Collectively Evaluated for Impairment	188,993	155,964
Total	189,108	156,084
Associated Allowance
Individually Evaluated for Impairment	0	0
Collectively Evaluated for Impairment	945	1,179
Total	945	1,179
Commercial And Financial [Member] | PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	1,217	1,312
Associated Allowance
Individually Evaluated for Impairment	0	0
Consumer [Member]
Carrying Value
Individually Evaluated for Impairment	636	599
Collectively Evaluated for Impairment	63,155	52,808
Total	63,791	53,407
Associated Allowance
Individually Evaluated for Impairment	94	112
Collectively Evaluated for Impairment	1,689	682
Total	1,783	794
Consumer [Member] | PCI Loans [Member]
Carrying Value
Individually Evaluated for Impairment	0	2
Associated Allowance
Individually Evaluated for Impairment	$ 0	$ 0