Fair Market Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	$ 593,746	$ 561,403
Equity securities at fair value	1,173	0
Assets measured-nonrecurring basis [Abstract]
Impaired loans (collateral dependent)	747	2,709
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)	$ 830	(361)
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]
Available-for-sale securities, debt securities	$ 217,938	210,572
State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	124,488	145,015
U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	250,819	205,309
Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	501	507
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	0
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	0
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	1,173
Recurring [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	1,173
Mortgage servicing rights	3,607	3,484
Recurring [Member] \| U.S. Treasury and Government Agencies [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	217,938	210,572
Recurring [Member] \| State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	124,488	145,015
Recurring [Member] \| U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	250,819	205,309
Recurring [Member] \| Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	501	507
Recurring [Member] \| CRA Investment Funds [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities		24,358
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
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]
Available-for-sale securities, debt securities	91,028	64,598
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]
Available-for-sale securities, debt securities	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]
Available-for-sale securities, debt securities	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]
Available-for-sale securities, debt securities	0	0
Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| CRA Investment Funds [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities		24,358
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	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]
Available-for-sale securities, debt securities	126,910	145,974
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	124,488	145,015
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]
Available-for-sale securities, debt securities	250,819	205,309
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	501	507
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| CRA Investment Funds [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities		0
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	1,173
Mortgage servicing rights	3,607	3,484
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| U.S. Treasury and Government Agencies [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	0	0
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	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]
Available-for-sale securities, debt securities	0	0
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities	0	0
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| CRA Investment Funds [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Available-for-sale securities, debt securities		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	0	0
Total unrealized gains Included in net income	1,173	0
Issues	0	0
Settlements	0	0
Ending balance	1,173	0
Total gains 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	1,173	0
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	3,484	3,433
Total unrealized gains Included in net income	73	91
Issues	466	412
Settlements	(416)	(452)
Ending balance	3,607	3,484
Total gains 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	73	91
Nonrecurring [Member]
Impaired loan (collateral dependent) [Abstract]
Impaired loans, fair value adjustments	300	1,000
Other real estate owned [Abstract]
Other real estate owned, fair value adjustment	1,800	2,500
Nonrecurring [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Impaired loans (collateral dependent)	747	2,709
Other real estate owned	6,500	18,951
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)	747	2,709
Other real estate owned	$ 6,500	$ 18,951

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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 unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

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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 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 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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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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