Loans - Summary of Impaired Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Recorded Investment
With No Allowance Recorded	$ 16,200	$ 15,900
Total	20,517	20,957
Unpaid Principal Balance
Total	23,205	23,132
Related Allowance	(62)	(142)
Real Estate \| Commercial
Recorded Investment
Total	16,927	17,327
Unpaid Principal Balance
Total	19,025	18,916
Related Allowance	(55)	(135)
Real Estate \| One-to-four family residential mortgage
Recorded Investment
Total	2,448	2,479
Unpaid Principal Balance
Total	2,568	2,595
Related Allowance	0	0
Real Estate \| Multifamily
Recorded Investment
Total	1,034	1,038
Unpaid Principal Balance
Total	1,505	1,508
Related Allowance	0	0
Real Estate \| Home equity and lines of credit
Recorded Investment
Total	53	55
Unpaid Principal Balance
Total	52	55
Related Allowance	(3)	(3)
Real Estate \| Home equity and lines of credit \| Substandard
Recorded Investment
With a Related Allowance Recorded	33	33
Unpaid Principal Balance
With a Related Allowance Recorded	32	33
Related Allowance	(3)	(3)
Real Estate \| Home equity and lines of credit \| Pass
Recorded Investment
With No Allowance Recorded	20	22
Unpaid Principal Balance
With No Allowance Recorded	20	22
Commercial and Industrial
Recorded Investment
Total	55	58
Unpaid Principal Balance
Total	55	58
Related Allowance	(4)	(4)
Commercial and Industrial \| Substandard
Recorded Investment
With No Allowance Recorded	37	39
Unpaid Principal Balance
With No Allowance Recorded	37	39
Commercial and Industrial \| Special Mention
Recorded Investment
With a Related Allowance Recorded	18	19
Unpaid Principal Balance
With a Related Allowance Recorded	18	19
Related Allowance	(4)	(4)
Less Than 35% LTV \| Real Estate \| Commercial \| Substandard
Recorded Investment
With No Allowance Recorded	0	0
Unpaid Principal Balance
With No Allowance Recorded	139	139
Less Than 35% LTV \| Real Estate \| Multifamily \| Substandard
Recorded Investment
With No Allowance Recorded	40	40
Unpaid Principal Balance
With No Allowance Recorded	40	40
Equal to or Greater than 35% LTV \| Real Estate \| Commercial \| Substandard
Recorded Investment
With No Allowance Recorded	10,883	10,438
With a Related Allowance Recorded	553	1,307
Unpaid Principal Balance
With No Allowance Recorded	11,089	11,002
With a Related Allowance Recorded	1,419	1,307
Related Allowance	(55)	(135)
Equal to or Greater than 35% LTV \| Real Estate \| Commercial \| Pass
Recorded Investment
With No Allowance Recorded	5,491	5,582
Unpaid Principal Balance
With No Allowance Recorded	6,378	6,468
Equal to or Greater than 35% LTV \| Real Estate \| Multifamily \| Substandard
Recorded Investment
With No Allowance Recorded	972	972
Unpaid Principal Balance
With No Allowance Recorded	972	972
Equal to or Greater than 35% LTV \| Real Estate \| Multifamily \| Pass
Recorded Investment
With No Allowance Recorded	22	26
Unpaid Principal Balance
With No Allowance Recorded	493	496
Less Than 60% LTV \| One-to-four family residential mortgage \| Special Mention
Recorded Investment
With No Allowance Recorded	382	385
Unpaid Principal Balance
With No Allowance Recorded	382	385
Less Than 60% LTV \| Real Estate \| One-to-four family residential mortgage \| Substandard
Recorded Investment
With No Allowance Recorded	556	564
With a Related Allowance Recorded	0	0
Unpaid Principal Balance
With No Allowance Recorded	556	564
With a Related Allowance Recorded	0	0
Related Allowance	0	0
Less Than 60% LTV \| Real Estate \| One-to-four family residential mortgage \| Pass
Recorded Investment
With No Allowance Recorded	1,363	1,379
Unpaid Principal Balance
With No Allowance Recorded	1,449	1,463
Equal to or Greater than 60% LTV \| Real Estate \| One-to-four family residential mortgage \| Substandard
Recorded Investment
With No Allowance Recorded	27	29
Unpaid Principal Balance
With No Allowance Recorded	27	29
Equal to or Greater than 60% LTV \| Real Estate \| One-to-four family residential mortgage \| Pass
Recorded Investment
With No Allowance Recorded	120	122
Unpaid Principal Balance
With No Allowance Recorded	$ 154	$ 154

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

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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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