Loans Receivable and Allowance for Loan Losses (Delinquency Status of Total Loans) (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	$ 17,015,000	$ 30,879,000
Current	2,312,622,000	2,299,139,000
Financing Receivable, Net, Total	2,329,637,000	2,330,018,000
Loans Receivable >90 Days and Accruing	651,000	333,000
30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	4,210,000	20,847,000
60 to 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	434,000	4,178,000
Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	12,371,000	5,854,000
Originated loans [Member] \| Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	615,000	1,437,000
Current	223,715,000	242,932,000
Financing Receivable, Net, Total	224,330,000	244,369,000
Loans Receivable >90 Days and Accruing		125,000
Originated loans [Member] \| Residential [Member] \| 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	463,000	507,000
Originated loans [Member] \| Residential [Member] \| 60 to 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due		266,000
Originated loans [Member] \| Residential [Member] \| Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	152,000	664,000
Originated loans [Member] \| Commercial & Multi-family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	9,039,000	20,240,000
Current	1,730,937,000	1,670,596,000
Financing Receivable, Net, Total	1,739,976,000	1,690,836,000
Loans Receivable >90 Days and Accruing	651,000
Originated loans [Member] \| Commercial & Multi-family [Member] \| 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	2,992,000	15,910,000
Originated loans [Member] \| Commercial & Multi-family [Member] \| 60 to 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due		2,996,000
Originated loans [Member] \| Commercial & Multi-family [Member] \| Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	6,047,000	1,334,000
Originated loans [Member] \| Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	2,787,000
Current	146,289,000	155,967,000
Financing Receivable, Net, Total	149,076,000	155,967,000
Loans Receivable >90 Days and Accruing
Originated loans [Member] \| Construction [Member] \| Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	2,787,000
Originated loans [Member] \| Commercial Business [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	4,509,000	8,147,000
Current	156,907,000	176,210,000
Financing Receivable, Net, Total	161,416,000	184,357,000
Loans Receivable >90 Days and Accruing		133,000
Originated loans [Member] \| Commercial Business [Member] \| 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	723,000	3,889,000
Originated loans [Member] \| Commercial Business [Member] \| 60 to 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	434,000	904,000
Originated loans [Member] \| Commercial Business [Member] \| Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	3,352,000	3,354,000
Originated loans [Member] \| Home Equity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	65,000	1,055,000
Current	52,044,000	52,612,000
Financing Receivable, Net, Total	52,109,000	53,667,000
Loans Receivable >90 Days and Accruing		75,000
Originated loans [Member] \| Home Equity [Member] \| 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	32,000	541,000
Originated loans [Member] \| Home Equity [Member] \| 60 to 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due		12,000
Originated loans [Member] \| Home Equity [Member] \| Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	33,000	502,000
Originated loans [Member] \| Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current	2,730,000	822,000
Financing Receivable, Net, Total	2,730,000	822,000
Loans Receivable >90 Days and Accruing