Fair Market Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	$ 997,261	$ 599,844
Equity securities at fair value	2,471	1,953
Liabilities Measured at Fair Value on Recurring Basis [Abstract]
Liabilities	0	0
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans	1,768
Impaired loans		3,217
Reconciliation of beginning and ending balances of recurring fair value measurements recognized in balance sheet using significant unobservable (Level 3) inputs [Roll Forward]
Total losses	$ (546)	(195)
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]
Debt securities available-for-sale	$ 148,793	171,150
State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	140,416	102,307
U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	651,807	295,245
Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	56,245	31,142
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	74,991	54,263
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]
Debt securities available-for-sale	922,270	545,581
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]
Debt securities available-for-sale	0	0
Equity securities at fair value	2,471	1,953
Recurring [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	2,471	1,953
Mortgage servicing rights	4,068	3,263
Recurring [Member] \| U.S. Treasury and Government Agencies [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	148,793	171,150
Recurring [Member] \| State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	140,416	102,307
Recurring [Member] \| U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	651,807	295,245
Recurring [Member] \| Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	56,245	31,142
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]
Debt securities available-for-sale	74,991	54,263
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]
Debt 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]
Debt 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]
Debt 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]
Debt securities available-for-sale	73,802	116,887
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	140,416	102,307
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]
Debt securities available-for-sale	651,807	295,245
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	56,245	31,142
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	2,471	1,953
Mortgage servicing rights	4,068	3,263
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| U.S. Treasury and Government Agencies [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt 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]
Debt 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]
Debt 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]
Debt 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	1,953	1,173
Total unrealized gains (losses) included in net income	518	780
Issues	0	0
Settlements	0	0
Ending balance	2,471	1,953
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	518	780
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	3,263	3,607
Total unrealized gains (losses) included in net income	(163)	(515)
Issues	1,869	631
Settlements	(901)	(460)
Ending balance	4,068	3,263
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	(163)	(515)
Nonrecurring [Member]
Collateral dependent loans [Abstract]
Fair value adjustments on collateral dependent loans	500	700
Other real estate owned [Abstract]
Other real estate owned, fair value adjustment	700	3,200
Nonrecurring [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans	1,768
Impaired loans		3,217
Other real estate owned	2,395	12,593
Nonrecurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans	0
Impaired loans		0
Other real estate owned	0	0
Nonrecurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans	0
Impaired loans		0
Other real estate owned	0	0
Nonrecurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans	1,768
Impaired loans		3,217
Other real estate owned	$ 2,395	$ 12,593

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This element represents the fair value disclosure of collateral dependent loan receivable as presented on the statement of financial position.

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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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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 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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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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