Allowance for Loan Losses (Summary of Loans Classified as TDRs) (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Performing Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan	9
Recorded Investment \| $	$ 319
Non Accruing Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan	1
Recorded Investment \| $	$ 20
Accruing Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan	8
Recorded Investment \| $	$ 299
Real Estate Loans: One-to-Four Family [Member] \| Performing Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan	8	5
Recorded Investment \| $	$ 304	$ 166
Real Estate Loans: One-to-Four Family [Member] \| Non Accruing Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan	1	1
Recorded Investment \| $	$ 20	$ 28
Real Estate Loans: One-to-Four Family [Member] \| Accruing Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan	7	4
Recorded Investment \| $	$ 284	$ 138
Real Estate Loans: Home Equity [Member] \| Performing Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan	1
Recorded Investment \| $	$ 15
Real Estate Loans: Home Equity [Member] \| Accruing Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan	1
Recorded Investment \| $	$ 15

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.

No definition available.

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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