Disclosures of Fair Values of Financial Instruments (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Available-for-sale: [Abstract]
Total available-for-sale securities	$ 686,048,000	$ 692,274,000
Impaired Loans Receivable [Abstract]
Carrying amount of loans with a specific allowance		19,481,000
Fair value of loans with a specific allowance		16,437,000
Specific Allowance		3,044,000
Fair Value, Measurements, Recurring [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	686,048,000	692,274,000
Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale: [Abstract]
Total available-for-sale securities	219,000	364,000
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2)
Available-for-sale: [Abstract]
Total available-for-sale securities	684,856,000	690,943,000
Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3)
Available-for-sale: [Abstract]
Total available-for-sale securities	973,000	967,000
Fair Value, Measurements, Nonrecurring [Member]
Impaired Loans Receivable [Abstract]
Carrying amount of loans with a specific allowance	13,775,000
Fair value of loans with a specific allowance	12,727,000
Specific Allowance	1,047,600
U.S. Treasury securities and obligations of U.S. government corporations & agencies
Available-for-sale: [Abstract]
Total available-for-sale securities	107,320,000	198,649,000
U.S. Treasury securities and obligations of U.S. government corporations & agencies \| Fair Value, Measurements, Recurring [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	107,320,000	198,649,000
U.S. Treasury securities and obligations of U.S. government corporations & agencies \| Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
U.S. Treasury securities and obligations of U.S. government corporations & agencies \| Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2)
Available-for-sale: [Abstract]
Total available-for-sale securities	107,320,000	198,649,000
U.S. Treasury securities and obligations of U.S. government corporations & agencies \| Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
Obligations of states and political subdivisions
Available-for-sale: [Abstract]
Total available-for-sale securities	178,433,000	192,579,000
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	967,000	0
Transfers into Level 3	0	967,000
Transfers out of Level 3	0	0
Total gains or losses [Abstract]
Included in net income	6,000	0
Included in other comprehensive income (loss)	0	0
Purchases, issuances, sales and settlements [Abstract]
Purchases	0	0
Issuances	0	0
Sales	0	0
Settlements	0	0
Ending balance	973,000	967,000
Total gains or losses for the period included in net income attributable to the change in unrealized gains or losses related to assets and liabilities still held at the reporting date	0	0
Obligations of states and political subdivisions \| Fair Value, Measurements, Recurring [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	178,433,000	192,579,000
Obligations of states and political subdivisions \| Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
Obligations of states and political subdivisions \| Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2)
Available-for-sale: [Abstract]
Total available-for-sale securities	177,460,000	191,612,000
Obligations of states and political subdivisions \| Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3)
Available-for-sale: [Abstract]
Total available-for-sale securities	973,000	967,000
Residential Mortgage Backed Securities [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	396,126,000	298,672,000
Residential Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	396,126,000	298,672,000
Residential Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
Residential Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2)
Available-for-sale: [Abstract]
Total available-for-sale securities	396,126,000	298,672,000
Residential Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3)
Available-for-sale: [Abstract]
Total available-for-sale securities	0	0
Trust preferred securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0	2,548,000
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Total gains or losses [Abstract]
Included in net income	0	0
Included in other comprehensive income (loss)	0	18,000
Purchases, issuances, sales and settlements [Abstract]
Purchases	0	0
Issuances	0	0
Sales	0	(2,522,000)
Settlements	0	(44,000)
Ending balance	0	0
Total gains or losses for the period included in net income attributable to the change in unrealized gains or losses related to assets and liabilities still held at the reporting date	0	0
Other securities
Available-for-sale: [Abstract]
Total available-for-sale securities	4,169,000	2,374,000
Other securities \| Fair Value, Measurements, Recurring [Member]
Available-for-sale: [Abstract]
Total available-for-sale securities	4,169,000	2,374,000
Other securities \| Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale: [Abstract]
Total available-for-sale securities	219,000	364,000
Other securities \| Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2)
Available-for-sale: [Abstract]
Total available-for-sale securities	3,950,000	2,010,000
Other securities \| Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3)
Available-for-sale: [Abstract]
Total available-for-sale securities	$ 0	$ 0

Amount of allowance for credit losses related to recorded investment measured at fair value on a nonrecurring basis.

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Amount of investment in impaired financing receivables, for which there is a related allowance for credit losses, measured at fair value on a nonrecurring basis.

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Unpaid principal balance of impaired financing receivables, for which there is a related allowance for credit losses, measured at fair value on a nonrecurring basis.

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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), classified as current.

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized loss realized upon the write-down of available-for-sale securities.

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