Loans - Impaired Loans, Individually Evaluated (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Impaired Loans [Abstract]
Unpaid Principal Balance	$ 9,174		$ 9,174		$ 12,526
Recorder Investment - Without Allowance	7,036		7,036		10,072
Recorder Investment - With Allowance	2,082		2,082		2,321
Total Recorded Investment	9,118		9,118		12,393
Related Allowance	446		446		724
Average Recorded Investment	9,100	$ 7,937	10,084	$ 8,148
Interest Income Recognized	140	96	325	216
Forgone interest on nonaccrual loans	62	74	126	165
Commercial business
Impaired Loans [Abstract]
Unpaid Principal Balance	616		616		997
Recorder Investment - Without Allowance	617		617		714
Recorder Investment - With Allowance	0		0		283
Total Recorded Investment	617		617		997
Related Allowance	0		0		84
Average Recorded Investment	1,076	694	1,174	1,103
Interest Income Recognized	12	0	12	20
One-to-four family \| Real estate loans:
Impaired Loans [Abstract]
Unpaid Principal Balance	6,122		6,122		8,748
Recorder Investment - Without Allowance	4,517		4,517		7,236
Recorder Investment - With Allowance	1,542		1,542		1,384
Total Recorded Investment	6,059		6,059		8,620
Related Allowance	207		207		205
Average Recorded Investment	6,027	4,011	6,650	3,831
Interest Income Recognized	69	65	208	125
Home equity \| Real estate loans:
Impaired Loans [Abstract]
Unpaid Principal Balance	294		294		335
Recorder Investment - Without Allowance	151		151		256
Recorder Investment - With Allowance	143		143		79
Total Recorded Investment	294		294		335
Related Allowance	18		18		25
Average Recorded Investment	336	1,998	341	1,302
Interest Income Recognized	3	14	12	23
Commercial and multifamily \| Real estate loans:
Impaired Loans [Abstract]
Unpaid Principal Balance	574		574		353
Recorder Investment - Without Allowance	577		577		353
Recorder Investment - With Allowance	0		0		0
Total Recorded Investment	577		577		353
Related Allowance	0		0		0
Average Recorded Investment	465	501	409	1,022
Interest Income Recognized	16	0	26	8
Construction and land \| Real estate loans:
Impaired Loans [Abstract]
Unpaid Principal Balance	592		592		1,215
Recorder Investment - Without Allowance	555		555		1,177
Recorder Investment - With Allowance	37		37		38
Total Recorded Investment	592		592		1,215
Related Allowance	6		6		7
Average Recorded Investment	315	121	579	273
Interest Income Recognized	20	1	21	3
Manufactured homes \| Consumer loans:
Impaired Loans [Abstract]
Unpaid Principal Balance	330		330		445
Recorder Investment - Without Allowance	90		90		46
Recorder Investment - With Allowance	243		243		394
Total Recorded Investment	333		333		440
Related Allowance	184		184		349
Average Recorded Investment	349	462	391	460
Interest Income Recognized	5	14	19	31
Floating homes \| Consumer loans:
Impaired Loans [Abstract]
Unpaid Principal Balance	529		529		290
Recorder Investment - Without Allowance	529		529		290
Recorder Investment - With Allowance	0		0		0
Total Recorded Investment	529		529		290
Related Allowance	0		0		0
Average Recorded Investment	405		406
Interest Income Recognized	15	0	23	0
Other consumer \| Consumer loans:
Impaired Loans [Abstract]
Unpaid Principal Balance	117		117		143
Recorder Investment - Without Allowance	0		0		0
Recorder Investment - With Allowance	117		117		143
Total Recorded Investment	117		117		143
Related Allowance	31		31		$ 54
Average Recorded Investment	127	150	134	157
Interest Income Recognized	$ 0	$ 2	$ 4	$ 6

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Amount of writeoff of accrued interest on financing receivable recognized by reversing interest income.

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