Borrowed Funds and Subordinated Debentures - Summary of Interest Rate Swaps (Details) - Interest Rate Swap		12 Months Ended
Feb. 16, 2019 USD ($)	Dec. 31, 2019 USD ($) contract	Dec. 31, 2018 USD ($) contract	Jul. 05, 2019 USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount		$ 60,000,000	$ 60,000,000	$ 10,000,000.0
Derivative instrument, maturity	$ 10,000,000
Fair value		$ 238,000	$ 1,433,000
Weighted average pay rate		1.42%	1.26%
Weighted average receive rate		2.19%	1.88%
Weighted average maturity in years		1 year 3 months 1 day	2 years 4 months 10 days
Number of contracts \| contract		4	4
(Decrease) increase in the fair value of interest rate swaps	$ (27,000)	$ (1,195,000)	$ 25,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Derivative Instrument, Maturity

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Weighted Average Receive Rate

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Weighted average interest rate of debt outstanding.

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Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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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.

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Amount of unrealized gain (loss) related to the fair value of interest rate derivatives designated as fair value hedging instruments, as offset by the gain (loss) on the hedged item to the extent that the fair value hedge is determined to be effective.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
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Number of interest rate derivative instruments held by the entity at the reporting date.

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