Fair Value Measurements - Summary of fair value measurements on recurring and non-recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale	$ (114,049)	$ (71,486)
OREO	575	705
Assets, fair value disclosure	118,571	76,496
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Assets, fair value disclosure	113,675	71,855
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Assets, fair value disclosure	4,896	4,641
U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale		(500)
Municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale	(29,413)	(12,475)
Agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale	(26,948)	(27,837)
Recurring \| U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale		(500)
Recurring \| U.S. Treasury securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale		(500)
Recurring \| Municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale	(29,413)	(12,475)
Recurring \| Municipal securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale	(29,413)	(12,475)
Recurring \| Agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale	(84,636)	(58,511)
Recurring \| Agency mortgage-backed securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale	(84,636)	(58,511)
Recurring \| Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale	(949)	(336)
Recurring \| Interest rate swap \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Securities available for sale	(949)	(336)
Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Maryland Financial Bank stock	3	3
Impaired loans	4,893	4,638
OREO	575	705
Nonrecurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
OREO	575	705
Nonrecurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Maryland Financial Bank stock	3	3
Impaired loans	$ 4,893	$ 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).

+ References

No definition available.

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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
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

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 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: 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=121558606&loc=SL82898722-210454

Reference 3: 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=121553693&loc=d3e26610-111562

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- References

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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5162-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4437-111522

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