FAIR VALUE - Changes in the assets subject to fair value measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$ (70,172)	$ (71,486)
Fair Value.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure	74,443	76,496
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure	69,843	71,855
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure	4,600	4,641
Collateralized mortgage obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(26,206)	(27,483)
Agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(29,312)	(27,837)
Municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(12,470)	(12,475)
U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(502)	(500)
Recurring \| Collateralized mortgage obligations \| Fair Value.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(26,206)	(27,483)
Recurring \| Collateralized mortgage obligations \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(26,206)	(27,483)
Recurring \| Agency mortgage-backed securities \| Fair Value.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(29,312)	(27,837)
Recurring \| Agency mortgage-backed securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(29,312)	(27,837)
Recurring \| Municipal securities \| Fair Value.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(12,470)	(12,475)
Recurring \| Municipal securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(12,470)	(12,475)
Recurring \| US Government Securities \| Fair Value.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(1,682)	(3,191)
Recurring \| US Government Securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(1,682)	(3,191)
Recurring \| U.S. Treasury securities \| Fair Value.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(502)	(500)
Recurring \| U.S. Treasury securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(502)	(500)
Recurring \| Interest rate swap \| Fair Value.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(1,034)	(336)
Recurring \| Interest rate swap \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	(1,034)	(336)
Nonrecurring \| Fair Value.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maryland Financial Bank stock	3	3
Impaired loans	4,597	4,638
OREO	705	705
Nonrecurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
OREO	705	705
Nonrecurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maryland Financial Bank stock	3	3
Impaired loans	$ 4,597	$ 4,638

Amount of fair value of loans and leases receivable Impaired as on the balance sheet date.

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- Definition

Maryland Financial Bank (MFB) stock represents an equity interest in a MFB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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No definition available.

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- Definition

Other real estate own fair value disclosure

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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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 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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