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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
		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.

X

- 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

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X

- 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

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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.

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