LOANS AND ALLOWANCE FOR LOAN LOSSES - Summary of Credit Exposure (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Financing Receivable Recorded Investment [Line Items]
Total loans	$ 1,655,703	$ 1,659,535	$ 1,401,334
Pass
Financing Receivable Recorded Investment [Line Items]
Total loans	1,642,967	1,642,415
Special Mention
Financing Receivable Recorded Investment [Line Items]
Total loans	4,261	6,641
Substandard
Financing Receivable Recorded Investment [Line Items]
Total loans	8,475	10,479
Commercial and industrial
Financing Receivable Recorded Investment [Line Items]
Total loans	246,176	261,779	206,308
Commercial and industrial | Pass
Financing Receivable Recorded Investment [Line Items]
Total loans	245,829	260,863
Commercial and industrial | Special Mention
Financing Receivable Recorded Investment [Line Items]
Total loans		224
Commercial and industrial | Substandard
Financing Receivable Recorded Investment [Line Items]
Total loans	347	692
Construction and development
Financing Receivable Recorded Investment [Line Items]
Total loans	250,852	237,503	193,909
Construction and development | Pass
Financing Receivable Recorded Investment [Line Items]
Total loans	249,602	236,253
Construction and development | Substandard
Financing Receivable Recorded Investment [Line Items]
Total loans	1,250	1,250
Commercial real estate
Financing Receivable Recorded Investment [Line Items]
Total loans	581,926	582,519	450,076
Commercial real estate | Pass
Financing Receivable Recorded Investment [Line Items]
Total loans	572,655	569,648
Commercial real estate | Special Mention
Financing Receivable Recorded Investment [Line Items]
Total loans	3,772	5,691
Commercial real estate | Substandard
Financing Receivable Recorded Investment [Line Items]
Total loans	5,499	7,180
Farmland
Financing Receivable Recorded Investment [Line Items]
Total loans	72,274	67,845	63,971
Farmland | Pass
Financing Receivable Recorded Investment [Line Items]
Total loans	71,977	67,541
Farmland | Special Mention
Financing Receivable Recorded Investment [Line Items]
Total loans	47	49
Farmland | Substandard
Financing Receivable Recorded Investment [Line Items]
Total loans	250	255
1-4 family residential
Financing Receivable Recorded Investment [Line Items]
Total loans	390,618	393,067	377,278
1-4 family residential | Pass
Financing Receivable Recorded Investment [Line Items]
Total loans	389,448	391,956
1-4 family residential | Special Mention
Financing Receivable Recorded Investment [Line Items]
Total loans	308	514
1-4 family residential | Substandard
Financing Receivable Recorded Investment [Line Items]
Total loans	862	597
Multi-family residential
Financing Receivable Recorded Investment [Line Items]
Total loans	37,430	38,386	37,992
Multi-family residential | Pass
Financing Receivable Recorded Investment [Line Items]
Total loans	37,430	38,386
Consumer and Overdrafts
Financing Receivable Recorded Investment [Line Items]
Total loans	56,433	55,159
Consumer and Overdrafts | Pass
Financing Receivable Recorded Investment [Line Items]
Total loans	56,375	55,055
Consumer and Overdrafts | Special Mention
Financing Receivable Recorded Investment [Line Items]
Total loans	20	48
Consumer and Overdrafts | Substandard
Financing Receivable Recorded Investment [Line Items]
Total loans	38	56
Agricultural
Financing Receivable Recorded Investment [Line Items]
Total loans	19,994	23,277	$ 22,545
Agricultural | Pass
Financing Receivable Recorded Investment [Line Items]
Total loans	19,651	22,713
Agricultural | Special Mention
Financing Receivable Recorded Investment [Line Items]
Total loans	114	115
Agricultural | Substandard
Financing Receivable Recorded Investment [Line Items]
Total loans	$ 229	$ 449