LOANS - Loans by Class Modified as Troubled Debt Restructurings (Details) $ in Thousands	Mar. 31, 2019 USD ($) contract	Dec. 31, 2018 USD ($) contract	Mar. 31, 2018 USD ($) contract
Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	12		8
Troubled debt restructuring loans | $	$ 2,161		$ 1,155
Purchased Loans By Class Modified
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	13		3
Troubled debt restructuring loans | $	$ 773		$ 186
Financing Receivables, 30 Days Past Due | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	7		19
Troubled debt restructuring loans | $	$ 837		$ 3,018
Financing Receivables, 30 Days Past Due | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	12		9
Troubled debt restructuring loans | $	$ 831		$ 906
Financing Receivables, 30 Days Past Due | Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	103	99
Troubled debt restructuring loans | $	$ 11,463	$ 9,323
Financing Receivables, 30 Days Past Due | Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	136	132
Troubled debt restructuring loans | $	$ 19,443	$ 18,740
Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	60	62
Troubled debt restructuring loans | $	$ 1,485	$ 1,754
Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	42	43
Troubled debt restructuring loans | $	$ 2,841	$ 3,451
Commercial, financial and agricultural | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	1		2
Troubled debt restructuring loans | $	$ 7		$ 125
Commercial, financial and agricultural | Purchased Loans By Class Modified
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	0		1
Troubled debt restructuring loans | $	$ 0		$ 7
Commercial, financial and agricultural | Financing Receivables, 30 Days Past Due | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	0		0
Troubled debt restructuring loans | $	$ 0		$ 0
Commercial, financial and agricultural | Financing Receivables, 30 Days Past Due | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	1		0
Troubled debt restructuring loans | $	$ 3		$ 0
Commercial, financial and agricultural | Financing Receivables, 30 Days Past Due | Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	3	5
Troubled debt restructuring loans | $	$ 116	$ 256
Commercial, financial and agricultural | Financing Receivables, 30 Days Past Due | Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	1	1
Troubled debt restructuring loans | $	$ 31	$ 31
Commercial, financial and agricultural | Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	14	14
Troubled debt restructuring loans | $	$ 138	$ 138
Commercial, financial and agricultural | Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	3	3
Troubled debt restructuring loans | $	$ 29	$ 32
Real estate – construction and development | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	0		1
Troubled debt restructuring loans | $	$ 0		$ 4
Real estate – construction and development | Purchased Loans By Class Modified
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	0		0
Troubled debt restructuring loans | $	$ 0		$ 0
Real estate – construction and development | Financing Receivables, 30 Days Past Due | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	0		0
Troubled debt restructuring loans | $	$ 0		$ 0
Real estate – construction and development | Financing Receivables, 30 Days Past Due | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	0		0
Troubled debt restructuring loans | $	$ 0		$ 0
Real estate – construction and development | Financing Receivables, 30 Days Past Due | Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	4	5
Troubled debt restructuring loans | $	$ 142	$ 145
Real estate – construction and development | Financing Receivables, 30 Days Past Due | Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	4	4
Troubled debt restructuring loans | $	$ 1,011	$ 1,015
Real estate – construction and development | Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	1	1
Troubled debt restructuring loans | $	$ 2	$ 2
Real estate – construction and development | Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	4	5
Troubled debt restructuring loans | $	$ 268	$ 293
Real estate – commercial and farmland | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	1		1
Troubled debt restructuring loans | $	$ 33		$ 303
Real estate – commercial and farmland | Purchased Loans By Class Modified
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	0		0
Troubled debt restructuring loans | $	$ 0		$ 0
Real estate – commercial and farmland | Financing Receivables, 30 Days Past Due | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	0		2
Troubled debt restructuring loans | $	$ 0		$ 1,971
Real estate – commercial and farmland | Financing Receivables, 30 Days Past Due | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	1		1
Troubled debt restructuring loans | $	$ 163		$ 351
Real estate – commercial and farmland | Financing Receivables, 30 Days Past Due | Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	13	12
Troubled debt restructuring loans | $	$ 2,954	$ 2,863
Real estate – commercial and farmland | Financing Receivables, 30 Days Past Due | Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	12	12
Troubled debt restructuring loans | $	$ 6,104	$ 6,162
Real estate – commercial and farmland | Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	4	3
Troubled debt restructuring loans | $	$ 450	$ 426
Real estate – commercial and farmland | Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	7	7
Troubled debt restructuring loans | $	$ 1,577	$ 1,685
Real estate – residential | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	7		2
Troubled debt restructuring loans | $	$ 2,109		$ 710
Real estate – residential | Purchased Loans By Class Modified
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	10		2
Troubled debt restructuring loans | $	$ 740		$ 179
Real estate – residential | Financing Receivables, 30 Days Past Due | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	7		17
Troubled debt restructuring loans | $	$ 837		$ 1,047
Real estate – residential | Financing Receivables, 30 Days Past Due | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	8		8
Troubled debt restructuring loans | $	$ 637		$ 555
Real estate – residential | Financing Receivables, 30 Days Past Due | Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	78	71
Troubled debt restructuring loans | $	$ 8,240	$ 6,043
Real estate – residential | Financing Receivables, 30 Days Past Due | Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	119	115
Troubled debt restructuring loans | $	$ 12,297	$ 11,532
Real estate – residential | Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	19	20
Troubled debt restructuring loans | $	$ 832	$ 1,119
Real estate – residential | Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	21	24
Troubled debt restructuring loans | $	$ 917	$ 1,424
Consumer installment | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	3		2
Troubled debt restructuring loans | $	$ 12		$ 13
Consumer installment | Purchased Loans By Class Modified
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	3		0
Troubled debt restructuring loans | $	$ 33		$ 0
Consumer installment | Financing Receivables, 30 Days Past Due | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	0		0
Troubled debt restructuring loans | $	$ 0		$ 0
Consumer installment | Financing Receivables, 30 Days Past Due | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	2		0
Troubled debt restructuring loans | $	$ 28		$ 0
Consumer installment | Financing Receivables, 30 Days Past Due | Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	5	6
Troubled debt restructuring loans | $	$ 11	$ 16
Consumer installment | Financing Receivables, 30 Days Past Due | Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	0	0
Troubled debt restructuring loans | $	$ 0	$ 0
Consumer installment | Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Loans Excluding Purchased Loan
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	22	24
Troubled debt restructuring loans | $	$ 63	$ 69
Consumer installment | Financing Receivables, 30 Days Past Due | Non-Accruing Loans | Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of contracts | contract	7	4
Troubled debt restructuring loans | $	$ 50	$ 17