ASSETS ACQUIRED IN FDIC-ASSISTED ACQUISITIONS - Components of Covered Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Covered Loans	$ 31,521	$ 61,269
Less Fair Value Adjustments	1,368	3,109
Total Covered Loans	30,153	58,160
OREO	187	1,212
Less Fair Value Adjustments	0	4
Total Covered OREO	187	1,208
Total Covered Assets	30,340	59,368
FDIC loss-share payable	(8,803)	(6,313)
American United Bank (“AUB”)
Business Acquisition [Line Items]
Covered Loans	0	0
Less Fair Value Adjustments	0	0
Total Covered Loans	0	0
OREO	0	0
Less Fair Value Adjustments	0	0
Total Covered OREO	0	0
Total Covered Assets	0	0
FDIC loss-share payable	(7)	(27)
United Security Bank (“USB”)
Business Acquisition [Line Items]
Covered Loans	2,626	3,199
Less Fair Value Adjustments	11	13
Total Covered Loans	2,615	3,186
OREO	0	51
Less Fair Value Adjustments	0	0
Total Covered OREO	0	51
Total Covered Assets	2,615	3,237
FDIC loss-share payable	(1,767)	(1,642)
Satilla Community Bank (“SCB”)
Business Acquisition [Line Items]
Covered Loans	2,237	4,019
Less Fair Value Adjustments	24	51
Total Covered Loans	2,213	3,968
OREO	0	0
Less Fair Value Adjustments	0	0
Total Covered OREO	0	0
Total Covered Assets	2,213	3,968
FDIC loss-share payable	(229)	(32)
First Bank of Jacksonville (“FBJ”)
Business Acquisition [Line Items]
Covered Loans	3,634	3,767
Less Fair Value Adjustments	375	452
Total Covered Loans	3,259	3,315
OREO	0	0
Less Fair Value Adjustments	0	0
Total Covered OREO	0	0
Total Covered Assets	3,259	3,315
FDIC loss-share payable	(330)	(234)
Darby Bank & Trust (“DBT”)
Business Acquisition [Line Items]
Covered Loans	8,995	12,166
Less Fair Value Adjustments	287	565
Total Covered Loans	8,708	11,601
OREO	81	0
Less Fair Value Adjustments	0	0
Total Covered OREO	81	0
Total Covered Assets	8,789	11,601
FDIC loss-share payable	(4,651)	(4,591)
Tifton Banking Company (“TBC”)
Business Acquisition [Line Items]
Covered Loans	1,498	1,679
Less Fair Value Adjustments	0	0
Total Covered Loans	1,498	1,679
OREO	0	0
Less Fair Value Adjustments	0	0
Total Covered OREO	0	0
Total Covered Assets	1,498	1,679
FDIC loss-share payable	(10)	(33)
High Trust Bank (“HTB”)
Business Acquisition [Line Items]
Covered Loans	1,844	1,913
Less Fair Value Adjustments	27	33
Total Covered Loans	1,817	1,880
OREO	0	0
Less Fair Value Adjustments	0	0
Total Covered OREO	0	0
Total Covered Assets	1,817	1,880
FDIC loss-share receivable	28	734
One Georgia Bank (“OGB”)
Business Acquisition [Line Items]
Covered Loans	920	1,077
Less Fair Value Adjustments	30	32
Total Covered Loans	890	1,045
OREO	0	0
Less Fair Value Adjustments	0	0
Total Covered OREO	0	0
Total Covered Assets	890	1,045
FDIC loss-share payable	(1,061)	(993)
Central Bank of Georgia (“CBG”)
Business Acquisition [Line Items]
Covered Loans	9,767	33,449
Less Fair Value Adjustments	614	1,963
Total Covered Loans	9,153	31,486
OREO	106	1,161
Less Fair Value Adjustments	0	4
Total Covered OREO	106	1,157
Total Covered Assets	9,259	32,643
FDIC loss-share payable	$ 776
FDIC loss-share receivable		$ 505