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Derivative Financial Instruments - Schedule of Notional Amount and Fair Value of Derivative Instruments Included on Company's Consolidated Balance Sheets on a net Basis (Details) - Derivatives Designated as Hedging Instruments [Member] - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
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Mar. 31, 2021 | Dec. 31, 2020
Derivatives Fair Value [Line Items] |  |  |
Estimated Fair Value Gain (Loss) | [1] | $ (1,701) | $ (2,610)
Fair Value Hedging [Member] |  |  |
Derivatives Fair Value [Line Items] |  |  |
Estimated Fair Value Gain (Loss) | [1] | (574) | (837)
Fair Value Hedging [Member] | Interest Rate Swaps Related to Fixed Rate Commercial Real Estate Loans [Member] |  |  |
Derivatives Fair Value [Line Items] |  |  |
Notional Amount |  | 20,000 | 20,000
Estimated Fair Value Gain (Loss) | [1] | (574) | (837)
Cash Flow Hedging [Member] |  |  |
Derivatives Fair Value [Line Items] |  |  |
Estimated Fair Value Gain (Loss) | [1] | (1,127) | (1,773)
Cash Flow Hedging [Member] | Interest Rate Swaps Related to Variable-Rate Money Market Deposit Accounts [Member] |  |  |
Derivatives Fair Value [Line Items] |  |  |
Notional Amount |  | 20,000 | 20,000
Estimated Fair Value Gain (Loss) | [1] | (832) | (1,337)
Cash Flow Hedging [Member] | Interest Rate Swaps Related to FHLB Advances [Member] |  |  |
Derivatives Fair Value [Line Items] |  |  |
Notional Amount |  | 10,000 | 10,000
Estimated Fair Value Gain (Loss) | [1] | $ (295) | $ (436)
[1] | Derivatives in a gain position are recorded as other assets and derivatives in a loss position are recorded as other liabilities on the consolidated balance sheets.

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959 + Details
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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959 + Details
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- Definition 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. + References No definition available. + Details
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- Details
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