INVESTMENT SECURITIES - Amortized cost and fair value of securities available-for-sale (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 48,257	$ 55,196
Gross Unrealized Gains	6	40
Gross Unrealized Losses	(2,771)	(1,586)
Fair Value	45,492	53,650
U.S. treasury and federal agency
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	250	250
Gross Unrealized Losses	(1)	(1)
Fair Value	249	249
Association (“GNMA”) mortgage-backed securities – residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	36,792	42,001
Gross Unrealized Gains	4	27
Gross Unrealized Losses	(2,274)	(1,192)
Fair Value	34,522	40,836
Securities issued by U.S. government sponsored entities and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	8,775	9,736
Gross Unrealized Gains		13
Gross Unrealized Losses	(494)	(296)
Fair Value	8,281	9,453
Corporate collateralized mortgage obligations and mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,423	1,529
Gross Unrealized Gains	2
Gross Unrealized Losses	(2)	(50)
Fair Value	1,423	1,479
Small Business Investment Company
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,017	930
Fair Value	$ 1,017	930
Equity mutual fund
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		750
Gross Unrealized Losses		(47)
Fair Value		$ 703

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

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