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Commercial Leases, Maturity

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Percent Threshold On Loan To Value Ratios Requiring Private Mortgage Insurance

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Projected Cash Flow To Loan Debt Service Requirement

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Amount of contractual principal due at origination of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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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.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Loans Receivable (Details) - USD ($)	12 Months Ended
Loans Receivable (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans receivable
Total loans	$ 1,174,728,000	$ 1,331,194,000
Net deferred loan origination costs	912,000	1,069,000
Allowance for loan losses	(7,632,000)	(8,470,000)	$ (8,366,000)
Loans, net	1,168,008,000	1,323,793,000
One-to-four family residential real estate loans [Member]
Loans receivable
Total loans	55,750,000	70,371,000
Allowance for loan losses	(675,000)	(699,000)	(850,000)
Multi-family mortgage loans [Member]
Loans receivable
Total loans	563,750,000	619,870,000
Allowance for loan losses	(3,676,000)	(3,991,000)	(3,849,000)
Nonresidential Real Estate [Member]
Loans receivable
Total loans	134,674,000	152,442,000
Allowance for loan losses	(1,176,000)	(1,476,000)
Construction and land loans [Member]
Loans receivable
Total loans	0	172,000
Allowance for loan losses		(4,000)
Commercial loans [Member]
Loans receivable
Total loans	145,714,000	187,406,000
Allowance for loan losses	(1,308,000)	(1,517,000)
Commercial leases [Member]
Loans receivable
Total loans	272,629,000	299,394,000
Allowance for loan losses	(757,000)	(755,000)	$ (655,000)
Consumer loans [Member]
Loans receivable
Total loans	2,211,000	1,539,000
Allowance for loan losses	(40,000)	(28,000)
Nonresidential real estate loans [Member]
Loans receivable
Total loans	$ 134,674,000	$ 152,442,000
No Public Rating [Member] \| Maximum [Member] \| Commercial leases [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Leases, Maturity	5 years
Collateralized Loan [Member] \| Multi-family mortgage loans [Member]
Loans receivable
Collateralized Loan Receivable, Percentage Of Collateral Located Outside Primary Market Area	57.00%
Collateralized Loan [Member] \| Nonresidential real estate loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Projected Cash Flow To Loan Debt Service Requirement	120.00%
Collateralized Loan [Member] \| Maximum [Member] \| Multi-family mortgage loans [Member]
Loans receivable
Total loans	$ 5,000,000.0
Collateralized Loan [Member] \| Maximum [Member] \| Nonresidential real estate loans [Member]
Loans receivable
Total loans	5,000,000.0
Collateralized Loan [Member] \| Minimum [Member] \| Multi-family mortgage loans [Member]
Loans receivable
Total loans	500,000
Collateralized Loan [Member] \| Minimum [Member] \| Nonresidential real estate loans [Member]
Loans receivable
Total loans	$ 500,000
Mortgage loans above $400,000 [Member] \| Collateralized Loan [Member] \| Multi-family mortgage loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Projected Cash Flow To Loan Debt Service Requirement	120.00%
Adjustable Rate And Fixed Rate Residential Mortgage [Member] \| $2,500,000 [Member] \| Maximum [Member] \| Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Face Amount of Mortgages	$ 2,500,000
First Mortgage [Member] \| Residential Mortgage [Member]
Loans receivable
Percent Threshold On Loan To Value Ratios Requiring Private Mortgage Insurance	80.00%