Loans - Average Recorded Investment and Interest Recognized on Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Average Recorded Investment
Total	$ 20,738	$ 21,918
Interest Income
Total	159	210
Real Estate \| Commercial
Average Recorded Investment
Total	17,128	17,751
Interest Income
Total	112	150
Real Estate \| One-to-four family residential mortgage
Average Recorded Investment
Total	2,464	2,672
Interest Income
Total	33	34
Real Estate \| Multifamily
Average Recorded Investment
Total	1,036	1,364
Interest Income
Total	13	25
Real Estate \| Home equity and lines of credit
Average Recorded Investment
Total	54	60
Interest Income
Total	1	1
Real Estate \| Home equity and lines of credit \| Pass
Average Recorded Investment
With No Allowance Recorded	21	27
Interest Income
With No Allowance Recorded	0	0
Real Estate \| Home equity and lines of credit \| Substandard
Average Recorded Investment
With a Related Allowance Recorded	33	33
Interest Income
With a Related Allowance Recorded	1	1
Commercial and Industrial
Average Recorded Investment
Total	56	71
Interest Income
Total	0	0
Commercial and Industrial \| Substandard
Average Recorded Investment
With No Allowance Recorded	38	50
Interest Income
With No Allowance Recorded	0	0
Commercial and Industrial \| Special Mention
Average Recorded Investment
With a Related Allowance Recorded	18	21
Interest Income
With a Related Allowance Recorded	0	0
Less Than 35% LTV \| Real Estate \| Multifamily \| Substandard
Average Recorded Investment
With No Allowance Recorded	40	100
Interest Income
With No Allowance Recorded	0	1
Equal to or Greater than 35% LTV \| Real Estate \| Commercial \| Pass
Average Recorded Investment
With No Allowance Recorded	5,537	5,888
Interest Income
With No Allowance Recorded	75	78
Equal to or Greater than 35% LTV \| Real Estate \| Commercial \| Substandard
Average Recorded Investment
With No Allowance Recorded	10,661	11,604
With a Related Allowance Recorded	930	259
Interest Income
With No Allowance Recorded	37	72
With a Related Allowance Recorded	0	0
Equal to or Greater than 35% LTV \| Real Estate \| Multifamily \| Pass
Average Recorded Investment
With No Allowance Recorded	24	37
Interest Income
With No Allowance Recorded	4	4
Equal to or Greater than 35% LTV \| Real Estate \| Multifamily \| Substandard
Average Recorded Investment
With No Allowance Recorded	972	1,227
Interest Income
With No Allowance Recorded	9	20
Less Than 60% LTV \| Real Estate \| One-to-four family residential mortgage \| Pass
Average Recorded Investment
With No Allowance Recorded	1,371	1,677
Interest Income
With No Allowance Recorded	16	22
Less Than 60% LTV \| Real Estate \| One-to-four family residential mortgage \| Substandard
Average Recorded Investment
With No Allowance Recorded	560	240
With a Related Allowance Recorded	0	502
Interest Income
With No Allowance Recorded	11	3
With a Related Allowance Recorded	0	5
Less Than 60% LTV \| Real Estate \| One-to-four family residential mortgage \| Special Mention
Average Recorded Investment
With No Allowance Recorded	384	0
Interest Income
With No Allowance Recorded	5	0
Equal to or Greater than 60% LTV \| Real Estate \| One-to-four family residential mortgage \| Pass
Average Recorded Investment
With No Allowance Recorded	121	128
Interest Income
With No Allowance Recorded	1	1
Equal to or Greater than 60% LTV \| Real Estate \| One-to-four family residential mortgage \| Substandard
Average Recorded Investment
With No Allowance Recorded	28	125
Interest Income
With No Allowance Recorded	$ 0	$ 3

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

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