SUBORDINATED DEFERRABLE INTEREST DEBENTURES - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2006	Dec. 31, 2005	Dec. 31, 2017
Securities Financing Transaction [Line Items]
Preferred stock, value, issued	$ 0							$ 0
First National Banc Statutory Trust I
Securities Financing Transaction [Line Items]
Preferred stock value authorized							$ 5,000,000
Preferred stock spread variable dividend rate							2.80%
Trust preferred securities interest rate	5.60%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 5,000,000
Long-term debt, gross	5,155,000
Common stock held in trust	$ 155,000
Prosperity Banking Capital Trust I
Securities Financing Transaction [Line Items]
Preferred stock value authorized					$ 5,000,000
Preferred stock spread variable dividend rate					2.57%
Trust preferred securities interest rate	4.97%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 5,000,000
Long-term debt, gross	5,155,000
Common stock held in trust	155,000
Subordinated debt obligations, net carrying value	$ 3,567,000
Prosperity Banking Capital Trust II
Securities Financing Transaction [Line Items]
Preferred stock value authorized					$ 4,500,000
Preferred stock spread variable dividend rate					3.15%
Trust preferred securities interest rate	5.97%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 4,500,000
Long-term debt, gross	4,640,000
Common stock held in trust	140,000
Subordinated debt obligations, net carrying value	$ 3,513,000
Prosperity Bank Statutory Trust III
Securities Financing Transaction [Line Items]
Preferred stock value authorized					$ 10,000,000
Preferred stock spread variable dividend rate					1.60%
Trust preferred securities interest rate	4.39%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 10,000,000
Long-term debt, gross	10,310,000
Common stock held in trust	310,000
Subordinated debt obligations, net carrying value	$ 5,989,000
Prosperity Bank Statutory Trust IV
Securities Financing Transaction [Line Items]
Preferred stock value authorized					$ 10,000,000
Preferred stock spread variable dividend rate					1.54%
Trust preferred securities interest rate	4.33%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 5,000,000
Long-term debt, gross	5,155,000
Common stock held in trust	310,000
Subordinated debt obligations, net carrying value	$ 3,372,000
Coastal Bankshares Statutory Trust One
Securities Financing Transaction [Line Items]
Preferred stock value authorized				$ 5,000,000
Preferred stock spread variable dividend rate				3.15%
Trust preferred securities interest rate	5.59%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 5,000,000
Long-term debt, gross	5,155,000
Common stock held in trust	155,000
Subordinated debt obligations, net carrying value	$ 4,013,000
Coastal Bankshares Statutory Trust Two
Securities Financing Transaction [Line Items]
Preferred stock value authorized				$ 10,000,000
Preferred stock spread variable dividend rate				1.60%
Trust preferred securities interest rate	4.39%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 10,000,000
Long-term debt, gross	10,310,000
Common stock held in trust	310,000
Subordinated debt obligations, net carrying value	$ 6,421,000
Merchants & Southern Statutory Trust I
Securities Financing Transaction [Line Items]
Preferred stock value authorized			$ 3,000,000
Preferred stock spread variable dividend rate			1.90%
Trust preferred securities interest rate	4.69%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 3,000,000
Long-term debt, gross	3,093,000
Common stock held in trust	93,000
Subordinated debt obligations, net carrying value	$ 2,068,000
Merchants & Southern Statutory Trust II
Securities Financing Transaction [Line Items]
Preferred stock value authorized			$ 3,000,000
Preferred stock spread variable dividend rate			1.50%
Trust preferred securities interest rate	4.29%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 3,000,000
Long-term debt, gross	3,093,000
Common stock held in trust	93,000
Subordinated debt obligations, net carrying value	$ 1,910,000
Atlantic BancGroup, Inc. Statutory Trust I
Securities Financing Transaction [Line Items]
Preferred stock value authorized		$ 3,000,000
Preferred stock spread variable dividend rate		1.50%
Trust preferred securities interest rate	4.29%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 3,000,000
Long-term debt, gross	3,093,000
Common stock held in trust	93,000
Subordinated debt obligations, net carrying value	$ 1,844,000
Jacksonville Statutory Trust I
Securities Financing Transaction [Line Items]
Preferred stock value authorized		$ 4,000,000
Preferred stock spread variable dividend rate		2.63%
Trust preferred securities interest rate	5.42%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 4,000,000
Long-term debt, gross	4,124,000
Common stock held in trust	124,000
Subordinated debt obligations, net carrying value	$ 3,191,000
Jacksonville Statutory Trust II
Securities Financing Transaction [Line Items]
Preferred stock value authorized		$ 3,000,000
Preferred stock spread variable dividend rate		1.73%
Trust preferred securities interest rate	4.52%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 3,000,000
Long-term debt, gross	3,093,000
Common stock held in trust	93,000
Subordinated debt obligations, net carrying value	$ 2,042,000
Jacksonville Bancorp, Inc. Statutory Trust III
Securities Financing Transaction [Line Items]
Preferred stock value authorized		$ 7,550,000
Preferred stock spread variable dividend rate		3.75%
Trust preferred securities interest rate	6.54%
Preferred stock maturity period	30 years
Preferred stock, value, outstanding	$ 7,550,000
Long-term debt, gross	7,784,000
Common stock held in trust	234,000
Subordinated debt obligations, net carrying value	$ 6,673,000
Cherokee Statutory Trust I
Securities Financing Transaction [Line Items]
Preferred stock spread variable dividend rate	1.50%
Trust preferred securities interest rate	4.29%
Preferred stock, value, outstanding	$ 3,093,000
Long-term debt, gross	3,000,000
Common stock held in trust	93,000
Subordinated debt obligations, net carrying value	2,315,000
Ameris Statutory Trust I
Securities Financing Transaction [Line Items]
Preferred stock spread variable dividend rate						1.63%
Long-term debt, gross						$ 37,114,000
Common stock held in trust	$ 1,114,000
Preferred stock, value, issued						$ 36,000,000
Preferred stock and debt rate percentage	4.42%