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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Loans - Composition of Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	$ 694,234		$ 621,907
Deferred fees	(3,531)		(2,020)
Total loans held-for-portfolio, gross	690,703		619,887
Allowance for loan losses	(6,031)	$ (5,893)	(5,640)	$ (5,370)	$ (5,577)	$ (5,774)
Total loans held-for-portfolio, net	684,672		614,247
CARES Act, PPP Loan
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio, gross	73,100
Real estate loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	506,447		510,262
Consumer loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	78,068		72,714
Commercial business loans
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	109,719		38,931
Allowance for loan losses	(501)	(395)	(331)	(509)	(424)	(356)
One-to-four family
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	137,988		149,393
Allowance for loan losses	(1,149)	(1,129)	(1,120)	(1,139)	(1,189)	(1,314)
One-to-four family \| Real estate loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	137,988		149,393
Home equity
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	19,286		23,845
Allowance for loan losses	(154)	(166)	(178)	(165)	(229)	(202)
Home equity \| Real estate loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	19,286		23,845
Commercial and multifamily
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	273,084		261,268
Allowance for loan losses	(1,991)	(1,918)	(1,696)	(1,467)	(1,035)	(1,638)
Commercial and multifamily \| Real estate loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	273,084		261,268
Construction and land
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	76,089		75,756
Allowance for loan losses	(623)	(499)	(492)	(464)	(996)	(431)
Construction and land \| Real estate loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	76,089		75,756
Manufactured homes
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	21,227		20,613
Allowance for loan losses	(362)	(482)	(480)	(463)	(511)	(427)
Manufactured homes \| Consumer loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	21,227		20,613
Floating homes
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	46,256		43,799
Allowance for loan losses	(324)	(318)	(283)	(262)	(254)	(265)
Floating homes \| Consumer loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	46,256		43,799
Other consumer
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	10,585		8,302
Allowance for loan losses	(127)	$ (121)	(112)	$ (120)	$ (120)	$ (112)
Other consumer \| Consumer loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	$ 10,585		$ 8,302