LOANS - Age analysis of past due loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 15, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Deferred loan (fees) cost, net	$ (2,114)	$ (1,739)
Total Loans	1,029,975	986,040	$ 198,440
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,200	3,200
Total Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	5,941	7,257
Total Past Due	10,631	12,315
Current	1,021,458	975,464
Deferred loan (fees) cost, net	(2,114)	(1,739)
Total Loans	1,029,975	986,040
Total Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,533	633
Deferred loan (fees) cost, net	0	0
Total Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	926	1,258
Deferred loan (fees) cost, net	0	0
Total Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,231	3,167
Deferred loan (fees) cost, net	0	0
Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	0	0
Total Past Due	1,231	3,167
Current	14,482	16,101
Total Loans	15,713	19,268
Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,231	3,167
Excluding Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	5,941	7,257
Total Past Due	9,400	9,148
Current	1,006,976	959,363
Deferred loan (fees) cost, net	(2,114)	(1,739)
Total Loans	1,014,262	966,772
Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,533	633
Deferred loan (fees) cost, net	0	0
Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	926	1,258
Deferred loan (fees) cost, net	0	0
Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Deferred loan (fees) cost, net	0	0
Commercial and industrial Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	75,748	74,181
Commercial and industrial Other [Member] | Total Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	2,824	4,170
Total Past Due	4,012	6,065
Current	71,736	68,116
Total Loans	75,748	74,181
Commercial and industrial Other [Member] | Total Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,108	27
Commercial and industrial Other [Member] | Total Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	34	203
Commercial and industrial Other [Member] | Total Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	46	1,665
Commercial and industrial Other [Member] | Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	0	0
Total Past Due	46	1,665
Current	1,057	99
Total Loans	1,103	1,764
Commercial and industrial Other [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial and industrial Other [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial and industrial Other [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	46	1,665
Commercial and industrial Other [Member] | Excluding Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	2,824	4,170
Total Past Due	3,966	4,400
Current	70,679	68,017
Total Loans	74,645	72,417
Commercial and industrial Other [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,108	27
Commercial and industrial Other [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	34	203
Commercial and industrial Other [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	221,878	170,404
Construction [Member] | Total Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	181	587
Total Past Due	181	656
Current	221,697	169,748
Total Loans	221,878	170,404
Construction [Member] | Total Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Construction [Member] | Total Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Construction [Member] | Total Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	69
Construction [Member] | Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	0	0
Total Past Due	0	69
Current	677	682
Total Loans	677	751
Construction [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Construction [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Construction [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	69
Construction [Member] | Excluding Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	181	587
Total Past Due	181	587
Current	221,020	169,066
Total Loans	221,201	169,653
Construction [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Construction [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Construction [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Multi-family residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	69,124	63,459
Multi-family residential [Member] | Total Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	0	0
Total Past Due	0	0
Current	69,124	63,459
Total Loans	69,124	63,459
Multi-family residential [Member] | Total Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Multi-family residential [Member] | Total Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Multi-family residential [Member] | Total Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Multi-family residential [Member] | Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	0	0
Total Past Due	0	0
Current	897	937
Total Loans	897	937
Multi-family residential [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Multi-family residential [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Multi-family residential [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Multi-family residential [Member] | Excluding Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	0	0
Total Past Due	0	0
Current	68,227	62,522
Total Loans	68,227	62,522
Multi-family residential [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Multi-family residential [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Multi-family residential [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial real estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	459,115	457,611
Commercial real estate [Member] | Total Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	1,832	1,074
Total Past Due	2,628	1,660
Current	456,487	455,951
Total Loans	459,115	457,611
Commercial real estate [Member] | Total Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	393	103
Commercial real estate [Member] | Total Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	82	483
Commercial real estate [Member] | Total Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	321	0
Commercial real estate [Member] | Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	0	0
Total Past Due	321	0
Current	5,449	7,579
Total Loans	5,770	7,579
Commercial real estate [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial real estate [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Commercial real estate [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	321	0
Commercial real estate [Member] | Excluding Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	1,832	1,074
Total Past Due	2,307	1,660
Current	451,038	448,372
Total Loans	453,345	450,032
Commercial real estate [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	393	103
Commercial real estate [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	82	483
Commercial real estate [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Loans to individuals & overdrafts [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	10,013	12,814
Loans to individuals & overdrafts [Member] | Total Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	155
Total Past Due	160	25
Current	9,853	12,789
Total Loans	10,013	12,814
Loans to individuals & overdrafts [Member] | Total Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	5	1
Loans to individuals & overdrafts [Member] | Total Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	24
Loans to individuals & overdrafts [Member] | Total Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Loans to individuals & overdrafts [Member] | Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	0	0
Total Past Due	0	0
Current	0	0
Total Loans	0	0
Loans to individuals & overdrafts [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Loans to individuals & overdrafts [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Loans to individuals & overdrafts [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Loans to individuals & overdrafts [Member] | Excluding Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	155
Total Past Due	160	25
Current	9,853	12,789
Total Loans	10,013	12,814
Loans to individuals & overdrafts [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	5	1
Loans to individuals & overdrafts [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	24
Loans to individuals & overdrafts [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
1-to-4 family residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	151,697	159,597
1-to-4 family residential [Member] | Total Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	505	386
Total Past Due	3,038	2,826
Current	148,659	156,771
Total Loans	151,697	159,597
1-to-4 family residential [Member] | Total Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	859	502
1-to-4 family residential [Member] | Total Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	810	505
1-to-4 family residential [Member] | Total Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	864	1,433
1-to-4 family residential [Member] | Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	0	0
Total Past Due	864	1,433
Current	6,354	6,755
Total Loans	7,218	8,188
1-to-4 family residential [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
1-to-4 family residential [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
1-to-4 family residential [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	864	1,433
1-to-4 family residential [Member] | Excluding Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	505	386
Total Past Due	2,174	1,393
Current	142,305	150,016
Total Loans	144,479	151,409
1-to-4 family residential [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	859	502
1-to-4 family residential [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	810	505
1-to-4 family residential [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
HELOC [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	44,514	49,713
HELOC [Member] | Total Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	444	1,040
Total Past Due	612	1,083
Current	43,902	48,630
Total Loans	44,514	49,713
HELOC [Member] | Total Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	168	0
HELOC [Member] | Total Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	43
HELOC [Member] | Total Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
HELOC [Member] | Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	0	0
Total Past Due	0	0
Current	48	49
Total Loans	48	49
HELOC [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
HELOC [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
HELOC [Member] | Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
HELOC [Member] | Excluding Purchase Credit Impairment Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Accrual Loans	444	1,040
Total Past Due	612	1,083
Current	43,854	48,581
Total Loans	44,466	49,664
HELOC [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	168	0
HELOC [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	43
HELOC [Member] | Excluding Purchase Credit Impairment Loans [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 0	$ 0