Loans - Loans Consisted (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Total loans	$ 381,521		$ 343,799
Net deferred loan (fees) costs	(33)		1,056
Allowance for loan losses	(3,153)	$ (3,009)	(2,875)	$ (2,832)	$ (2,806)	$ (2,806)
Net loans	378,335		341,980
CRE [Member]
Total loans	69,068		70,194
Allowance for loan losses	(740)	(796)	(781)	(722)	(644)	(560)
MF [Member]
Total loans	6,425		4,888
Allowance for loan losses	(52)	(48)	(23)	(22)	(21)	(22)
C+I [Member]
Total loans	53,696		24,676
Allowance for loan losses	(278)	(287)	(350)	(216)	(220)	(232)
ADL [Member]
Total loans	23,637		18,844
Allowance for loan losses	(223)	(135)	(145)	(82)	(143)	(88)
RES [Member]
Total loans	217,376		213,322
Allowance for loan losses	(1,690)	(1,643)	(1,503)	(1,728)	(1,585)	(1,593)
HELOC [Member]
Total loans	9,359		10,123
Allowance for loan losses	(58)	(79)	(52)	(54)	(51)	(69)
CON [Member]
Total loans	1,960		1,752
Allowance for loan losses	$ (29)	$ (20)	$ (18)	$ (9)	$ (5)	$ (7)

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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