Loans Receivable - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 7,632	$ 8,470
Loans charged off	(18)	(56)
Recoveries	27	27
Provision for (recovery of) loan losses	(471)	87
Ending balance	8,112	8,354
One-to-four family residential real estate loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	675	699
Loans charged off	(5)	(23)
Recoveries	13	17
Provision for (recovery of) loan losses	1	44
Ending balance	682	649
Multi-family mortgage loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	3,676	3,991
Loans charged off	0	0
Recoveries	12	8
Provision for (recovery of) loan losses	(181)	(80)
Ending balance	3,869	4,079
Nonresidential real estate loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,176	1,476
Loans charged off	0	(28)
Provision for (recovery of) loan losses	(284)	(39)
Ending balance	1,460	1,487
Construction and land loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	0	4
Provision for (recovery of) loan losses	0	1
Ending balance	0	3
Commercial loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,308
Loans charged off	0	0
Recoveries	2	2
Ending balance	1,275
Commercial leases [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	757	755
Recoveries	0	0
Provision for (recovery of) loan losses	(23)	65
Ending balance	780	690
Consumer loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	40
Loans charged off	(13)	(5)
Recoveries	0	$ 0
Ending balance	$ 46

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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-Publisher FASB
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- Definition

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.

+ References

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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