Loans Receivable, Part I (Details) $ in Thousands	Jun. 30, 2020 USD ($) Loan	Dec. 31, 2019 USD ($) Loan
Mortgage Loans [Abstract]
Loans receivable	$ 1,433,803	$ 1,388,031
Loans receivable pledged as collateral	1,080	1,070
Advances by Federal Home Loan Bank	574,000	470,000
Loans outstanding to related parties	$ 6,400	$ 6,300
Number of loans impaired \| Loan	0	0
Residential Real Estate [Member] \| One-to-Four Family [Member]
Mortgage Loans [Abstract]
Loans receivable	$ 467,346	$ 480,280
Residential Real Estate [Member] \| Multi Family [Member]
Mortgage Loans [Abstract]
Loans receivable	598,924	584,859
Residential Real Estate [Member] \| Home Equity [Member]
Mortgage Loans [Abstract]
Loans receivable	16,409	18,071
Construction and Land [Member]
Mortgage Loans [Abstract]
Loans receivable	48,850	37,033
Commercial Real Estate [Member]
Mortgage Loans [Abstract]
Loans receivable	244,775	236,703
Consumer [Member]
Mortgage Loans [Abstract]
Loans receivable	860	832
Commercial Loans [Member]
Mortgage Loans [Abstract]
Loans receivable	$ 56,639	$ 30,253

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- Definition

Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

+ References

No definition available.

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- Definition

Reflects the aggregate value of loans, trade receivables, securities and financial instruments that serve as collateral for obligations arising from a transfer of financial assets recorded as a secured borrowing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5086-111524

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

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- Definition

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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Refers to the number of loans that were considered impaired.

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