Loans Receivable and Allowance for Loan Losses (Recorded Investment in Loans Receivable) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross	$ 2,333,263	$ 2,330,018	$ 2,190,677
Deferred loan fees, net	(1,352)	(1,358)
Allowance for loan losses	(35,477)	(33,639)
Sub-total	(36,829)	(34,997)
Net Loans	2,296,434	2,295,021
Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross	234,375	244,369	268,137
Commercial & Multi-family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross	1,700,113	1,690,836	1,577,816
Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross	167,224	155,967	101,692
Commercial Business [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross	177,340	184,357	177,146
Home Equity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross	53,360	53,667	64,857
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross	$ 851	$ 822	$ 1,029

Total deductions from gross loans

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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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