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 Held-for-Portfolio, Excluding Loans Held for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	$ 627,269	$ 621,907
Deferred fees	(1,894)	(2,020)
Total loans held-for-portfolio, gross	625,375	619,887
Allowance for loan losses	(5,893)	(5,640)	$ (5,577)	$ (5,774)
Total loans held-for-portfolio, net	619,482	614,247
Real estate loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	513,563	510,262
Consumer loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	77,147	72,714
Commercial business loans
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	36,559	38,931
Allowance for loan losses	(395)	(331)	(424)	(356)
One-to-four family
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	140,525	149,393
Allowance for loan losses	(1,129)	(1,120)	(1,189)	(1,314)
One-to-four family \| Real estate loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	140,525	149,393
Home equity
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	20,981	23,845
Allowance for loan losses	(166)	(178)	(229)	(202)
Home equity \| Real estate loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	20,981	23,845
Commercial and multifamily
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	280,046	261,268
Allowance for loan losses	(1,918)	(1,696)	(1,035)	(1,638)
Commercial and multifamily \| Real estate loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	280,046	261,268
Construction and land
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	72,011	75,756
Allowance for loan losses	(499)	(492)	(996)	(431)
Construction and land \| Real estate loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	72,011	75,756
Manufactured homes
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	21,054	20,613
Allowance for loan losses	(482)	(480)	(511)	(427)
Manufactured homes \| Consumer loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	21,054	20,613
Floating homes
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	46,834	43,799
Allowance for loan losses	(318)	(283)	(254)	(265)
Floating homes \| Consumer loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	46,834	43,799
Other consumer
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	9,259	8,302
Allowance for loan losses	(121)	(112)	$ (120)	$ (112)
Other consumer \| Consumer loans:
Composition of Loans Held-for-Portfolio [Abstract]
Total loans held-for-portfolio	$ 9,259	$ 8,302