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LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES - Current, past due, and non-accrual loans by categories of loans and restructured loans (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	$ 278,986	$ 295,421
Past Due	700
Non-accrual	4,229	1,947	$ 4,685	$ 3,270
Total	283,889	299,120
30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	652	1,726
Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days or More and Still Accruing	22	26
Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	12,171	12,669
Non-accrual	144	186	122	185
Total	12,369	13,071
Consumer \| 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	54	216
Residential Real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	79,370	80,923
Non-accrual	756	956	1,753	2,124
Total	80,211	82,637
Residential Real estate \| 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	63	732
Residential Real estate \| Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days or More and Still Accruing	22	26
Indirect
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	105,517	115,890
Non-accrual	36	116	129	88
Total	106,088	116,698
Indirect \| 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	535	692
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	11,350	14,171
Non-accrual		27		48
Total	11,350	14,284
Commercial \| 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		86
Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	3,161	2,317
Non-accrual				318
Total	3,161	2,317
Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	67,417	69,451
Non-accrual	3,293	662	$ 2,371	$ 507
Total	$ 70,710	$ 70,113