Fair Market Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	$ 599,844	$ 593,746
Equity securities at fair value	1,953	1,173
Liabilities Measured at Fair Value on Recurring Basis [Abstract]
Liabilities	0	0
Transfers between Levels [Abstract]
Transfers from Level 1 to Level 2	0
Transfers from Level 2 to Level 1	0
Transfers into Level 3	0
Transfers out of Level 3	0
Assets measured-nonrecurring basis [Abstract]
Impaired loans (collateral dependent)	3,217	747
Reconciliation of beginning and ending balances of recurring fair value measurements recognized in balance sheet using significant unobservable (Level 3) inputs [Roll Forward]
Total gains (losses)	$ (195)	830
Minimum [Member]
Other real estate owned [Abstract]
Typical frequency of periodic reviews	12 months
Maximum [Member]
Other real estate owned [Abstract]
Typical frequency of periodic reviews	18 months
Frequency of periodic reviews in general	24 months
U.S. Treasury and Government Agencies [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	$ 171,150	217,938
State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	102,307	124,488
U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	295,245	250,819
Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	31,142	501
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	54,263	91,028
Equity securities at fair value	0	0
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	545,581	502,718
Equity securities at fair value	0	0
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	0	0
Equity securities at fair value	1,953	1,173
Recurring [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	1,953	1,173
Mortgage servicing rights	3,263	3,607
Recurring [Member] \| U.S. Treasury and Government Agencies [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	171,150	217,938
Recurring [Member] \| State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	102,307	124,488
Recurring [Member] \| U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	295,245	250,819
Recurring [Member] \| Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	31,142	501
Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	0	0
Mortgage servicing rights	0	0
Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| U.S. Treasury and Government Agencies [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	54,263	91,028
Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	0	0
Mortgage servicing rights	0	0
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| U.S. Treasury and Government Agencies [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	116,887	126,910
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	102,307	124,488
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	295,245	250,819
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	31,142	501
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	1,953	1,173
Mortgage servicing rights	3,263	3,607
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| U.S. Treasury and Government Agencies [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Securities available-for-sale	0	0
Recurring [Member] \| Equity Securities at Fair Value [Member]
Reconciliation of beginning and ending balances of recurring fair value measurements recognized in balance sheet using significant unobservable (Level 3) inputs [Roll Forward]
Beginning balance	1,173	0
Total unrealized gains (losses) included in net income	780	1,173
Issues	0	0
Settlements	0	0
Ending balance	1,953	1,173
Total gains (losses) for the period included in net income attributable to the change in unrealized gains or losses related to assets still held at the reporting date	780	1,173
Recurring [Member] \| Mortgage Servicing Rights [Member]
Reconciliation of beginning and ending balances of recurring fair value measurements recognized in balance sheet using significant unobservable (Level 3) inputs [Roll Forward]
Beginning balance	3,607	3,484
Total unrealized gains (losses) included in net income	(515)	73
Issues	631	466
Settlements	(460)	(416)
Ending balance	3,263	3,607
Total gains (losses) for the period included in net income attributable to the change in unrealized gains or losses related to assets still held at the reporting date	(515)	73
Nonrecurring [Member]
Impaired loan (collateral dependent) [Abstract]
Impaired loans, fair value adjustments	700	300
Other real estate owned [Abstract]
Other real estate owned, fair value adjustment	3,200	1,800
Nonrecurring [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Impaired loans (collateral dependent)	3,217	747
Other real estate owned	12,593	6,500
Nonrecurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Impaired loans (collateral dependent)	0	0
Other real estate owned	0	0
Nonrecurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Impaired loans (collateral dependent)	0	0
Other real estate owned	0	0
Nonrecurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Impaired loans (collateral dependent)	3,217	747
Other real estate owned	$ 12,593	$ 6,500

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The amount at which an asset could be bought or sold in a current transaction between willing parties, that is, other than in a forced or liquidation sale.

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No definition available.

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The amount at which an asset could be bought or sold in a current transaction between willing parties, that is, other than in a forced or liquidation sale.

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This element represents the fair value disclosure of impaired loan receivable as presented on the statement of financial position which may include mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts, or any other loans which are due the Company as of the balance sheet date.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents mortgage servicing right at fair value.

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The frequency of periodic reviews for appraisals on foreclosed properties and other real estate owned generally, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The typical frequency of periodic reviews for appraisals on foreclosed properties and other real estate owned, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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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 settlement 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 transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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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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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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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting.

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