Fair Value Measurements - Summary of fair value measurements on recurring and non-recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	$ 81,572	$ 89,349
OREO	705	114
Assets, fair value disclosure	85,078	93,074
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Assets, fair value disclosure	82,572	89,511
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Assets, fair value disclosure	2,506	3,562
U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	990	1,493
Municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	33,830	35,633
Agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	24,987	25,229
Recurring \| U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	990	1,493
Recurring \| U.S. Treasury securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	990	1,493
Recurring \| Municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	33,830	35,633
Recurring \| Municipal securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	33,830	35,633
Recurring \| Agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	46,752	52,223
Recurring \| Agency mortgage-backed securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	46,752	52,223
Recurring \| Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	295	49
Recurring \| Interest rate swap \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Investment securities available for sale, at fair value	295	49
Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Maryland Financial Bank stock	5	30
Impaired loans	2,501	3,532
OREO	705	114
Nonrecurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
OREO	705	114
Nonrecurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Maryland Financial Bank stock	5	30
Impaired loans	$ 2,501	$ 3,532

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

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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=99377789&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 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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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=84173941&loc=d3e5162-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4437-111522

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