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Loans - Summary of Impaired Loans (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Recorded Investment
With No Allowance Recorded	$ 7,800
Total	13,242
Unpaid Principal Balance
Total	15,512
Related Allowance	(73)
Real estate loans:
Recorded Investment
With No Allowance Recorded	11,382
With a Related Allowance Recorded	1,844
Unpaid Principal Balance
With No Allowance Recorded	13,220
With a Related Allowance Recorded	2,276
Related Allowance	(69)
Real estate loans: | Commercial mortgage
Recorded Investment
With No Allowance Recorded	8,838
With a Related Allowance Recorded	1,812
Total	10,650
Unpaid Principal Balance
With No Allowance Recorded	10,076
With a Related Allowance Recorded	2,244
Total	12,320
Related Allowance	(66)
Real estate loans: | One-to-four family residential mortgage
Recorded Investment
With No Allowance Recorded	1,903
Total	1,903
Unpaid Principal Balance
With No Allowance Recorded	2,032
Total	2,032
Related Allowance	0
Real estate loans: | Multifamily
Recorded Investment
With No Allowance Recorded	626
Total	626
Unpaid Principal Balance
With No Allowance Recorded	1,097
Total	1,097
Related Allowance	0
Real estate loans: | Home equity and lines of credit
Recorded Investment
With No Allowance Recorded	15
With a Related Allowance Recorded	32
Total	47
Unpaid Principal Balance
With No Allowance Recorded	15
With a Related Allowance Recorded	32
Total	47
Related Allowance	(3)
Commercial and industrial loans
Recorded Investment
With a Related Allowance Recorded	16
Total	16
Unpaid Principal Balance
With a Related Allowance Recorded	16
Total	16
Related Allowance	$ (4)

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