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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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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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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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No definition available.

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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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No definition available.

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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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No definition available.

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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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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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Fair Market Value of Financial Assets and Liabilities (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	$ 1,155,195,000	$ 997,261,000
Equity securities at fair value	2,243,000	2,471,000
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans	563,000	1,768,000
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)	$ 552,000		$ (1,159,000)
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	$ 203,619,000	148,793,000
State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	220,117,000	140,416,000
U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	674,832,000	651,807,000
Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	56,627,000	56,245,000
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	134,598,000	74,991,000
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	1,020,597,000	922,270,000
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	2,243,000	2,471,000
Recurring [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	2,243,000	2,471,000
Mortgage servicing rights	5,584,000	4,068,000
Recurring [Member] \| U.S. Treasury and Government Agencies [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	203,619,000	148,793,000
Recurring [Member] \| State and Political Subdivisions [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	220,117,000	140,416,000
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	674,832,000	651,807,000
Recurring [Member] \| Other Debt Securities [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Debt securities available-for-sale	56,627,000	56,245,000
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	134,598,000	74,991,000
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	69,021,000	73,802,000
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	220,117,000	140,416,000
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	674,832,000	651,807,000
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	56,627,000	56,245,000
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Assets Measured at Fair Value on Recurring Basis [Abstract]
Equity securities at fair value	2,243,000	2,471,000
Mortgage servicing rights	5,584,000	4,068,000
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 [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	2,471,000		1,953,000
Total unrealized gains (losses) included in net income	(228,000)		(232,000)
Issues	0		0
Settlements	0		0
Ending balance	2,243,000	2,471,000	1,721,000
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	(228,000)		(232,000)
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	4,068,000		3,263,000
Total unrealized gains (losses) included in net income	1,030,000		(818,000)
Issues	736,000		144,000
Settlements	(250,000)		(108,000)
Ending balance	5,584,000	4,068,000	2,481,000
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	1,030,000		(818,000)
Nonrecurring [Member]
Impaired loan (collateral dependent) [Abstract]
Fair value adjustments on collateral dependent loans	300,000	0.0	800,000
Other real estate owned [Abstract]
Other real estate owned, fair value adjustment	200,000	100,000	$ 400,000
Nonrecurring [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans	563,000	1,768,000
Other real estate owned	530,000	2,395,000
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	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	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	563,000	1,768,000
Other real estate owned	$ 530,000	$ 2,395,000