Fair Value Measurement - Summary of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Assets [Abstract]
Available for sale securities	$ 84,590	$ 79,783
Obligations of U.S. Government Corporations and Agencies [Member]
Assets [Abstract]
Available for sale securities	63,815	63,941
Obligations of States and Political Subdivisions [Member]
Assets [Abstract]
Available for sale securities	20,775	15,842
Fair Value on a Recurring Basis [Member]
Assets [Abstract]
Available for sale securities	84,590	79,783
Mutual funds	419	403
Total	85,009	80,186
Liabilities [Abstract]
Interest rate swaps	634	140
Total	634	140
Fair Value on a Recurring Basis [Member] \| Obligations of U.S. Government Corporations and Agencies [Member]
Assets [Abstract]
Available for sale securities	63,815	63,941
Fair Value on a Recurring Basis [Member] \| Obligations of States and Political Subdivisions [Member]
Assets [Abstract]
Available for sale securities	20,775	15,842
Level 1 [Member]
Assets [Abstract]
Available for sale securities	0	0
Mutual funds	419	403
Total	74,092	46,744
Liabilities [Abstract]
Interest rate swaps	0	0
Total	0	0
Level 1 [Member] \| Fair Value on a Recurring Basis [Member]
Assets [Abstract]
Available for sale securities	0	0
Mutual funds	419	403
Total	419	403
Liabilities [Abstract]
Interest rate swaps	0	0
Total	0	0
Level 1 [Member] \| Fair Value on a Recurring Basis [Member] \| Obligations of U.S. Government Corporations and Agencies [Member]
Assets [Abstract]
Available for sale securities	0	0
Level 1 [Member] \| Fair Value on a Recurring Basis [Member] \| Obligations of States and Political Subdivisions [Member]
Assets [Abstract]
Available for sale securities	0	0
Level 2 [Member]
Assets [Abstract]
Available for sale securities	84,590	79,783
Mutual funds	0	0
Total	103,526	97,991
Liabilities [Abstract]
Interest rate swaps	634	140
Total	758,334	643,822
Level 2 [Member] \| Fair Value on a Recurring Basis [Member]
Assets [Abstract]
Available for sale securities	84,590	79,783
Mutual funds	0	0
Total	84,590	79,783
Liabilities [Abstract]
Interest rate swaps	634	140
Total	634	140
Level 2 [Member] \| Fair Value on a Recurring Basis [Member] \| Obligations of U.S. Government Corporations and Agencies [Member]
Assets [Abstract]
Available for sale securities	63,815	63,941
Level 2 [Member] \| Fair Value on a Recurring Basis [Member] \| Obligations of States and Political Subdivisions [Member]
Assets [Abstract]
Available for sale securities	20,775	15,842
Level 3 [Member]
Assets [Abstract]
Available for sale securities	0	0
Mutual funds	0	0
Total	630,236	541,367
Liabilities [Abstract]
Interest rate swaps	0	0
Total	0	0
Level 3 [Member] \| Fair Value on a Recurring Basis [Member]
Assets [Abstract]
Available for sale securities	0	0
Mutual funds	0	0
Total	0	0
Liabilities [Abstract]
Interest rate swaps	0	0
Total	0	0
Level 3 [Member] \| Fair Value on a Recurring Basis [Member] \| Obligations of U.S. Government Corporations and Agencies [Member]
Assets [Abstract]
Available for sale securities	0	0
Level 3 [Member] \| Fair Value on a Recurring Basis [Member] \| Obligations of States and Political Subdivisions [Member]
Assets [Abstract]
Available for sale securities	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

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