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Fair Value Measurements - Quantitative and Qualitative Information (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	$ 11,461	$ 7,097
Securities available-for-sale, at fair value	1,609,759	1,693,632
Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	11,461	7,097
Securities available-for-sale, at fair value	13,309	15,236
States and political subdivisions
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	224,259	257,609
Collateralized mortgage obligations
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	587,846	672,967
Fair Value, Measurements, Recurring [Member]
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	11,461	7,097
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	11,461	7,097
Fair Value, Measurements, Recurring [Member] | Mortgage Servicing Rights [Member] | Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	11,461	7,097
Fair Value, Measurements, Recurring [Member] | States and political subdivisions
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	224,259	257,609
Fair Value, Measurements, Recurring [Member] | States and political subdivisions | Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	13,309	15,236
Fair Value, Measurements, Recurring [Member] | Collateralized mortgage obligations
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	$ 587,846	$ 672,967
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Mortgage Servicing Rights [Member] | Fair Value, Inputs, Level 3 [Member] | Minimum
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	0.090
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Mortgage Servicing Rights [Member] | Fair Value, Inputs, Level 3 [Member] | Maximum
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	0.110
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Mortgage Servicing Rights [Member] | Fair Value, Inputs, Level 3 [Member] | Weighted Average [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	0.090
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Mortgage Servicing Rights [Member] | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Minimum
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input		11.0
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Mortgage Servicing Rights [Member] | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Maximum
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input		15.0
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Mortgage Servicing Rights [Member] | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Weighted Average [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input		11.0
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | States and political subdivisions | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Minimum
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input		0.6
Debt Securities, Measurement Input	2.9
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | States and political subdivisions | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Maximum
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input		3.5
Debt Securities, Measurement Input	5.4
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | States and political subdivisions | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Weighted Average [Member]
Quantitative information about Level 3 fair value measurements
Debt Securities, Measurement Input	4.8	2.8
Fair Value, Measurements, Recurring [Member] | Measurement Input, Constant Prepayment Rate | Mortgage Servicing Rights [Member] | Fair Value, Inputs, Level 3 [Member] | Minimum
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	0.000
Fair Value, Measurements, Recurring [Member] | Measurement Input, Constant Prepayment Rate | Mortgage Servicing Rights [Member] | Fair Value, Inputs, Level 3 [Member] | Maximum
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	0.128
Fair Value, Measurements, Recurring [Member] | Measurement Input, Constant Prepayment Rate | Mortgage Servicing Rights [Member] | Fair Value, Inputs, Level 3 [Member] | Weighted Average [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	0.061
Fair Value, Measurements, Recurring [Member] | Measurement Input, Constant Prepayment Rate | Mortgage Servicing Rights [Member] | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Minimum
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input		0.0
Fair Value, Measurements, Recurring [Member] | Measurement Input, Constant Prepayment Rate | Mortgage Servicing Rights [Member] | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Maximum
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input		36.6
Fair Value, Measurements, Recurring [Member] | Measurement Input, Constant Prepayment Rate | Mortgage Servicing Rights [Member] | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Weighted Average [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input		11.9
Fair Value, Measurements, Recurring [Member] | Measurement Input, Liquidity Premium | States and political subdivisions | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Minimum
Quantitative information about Level 3 fair value measurements
Liquidity Premium (as a percent)	0.40%	0.30%
Fair Value, Measurements, Recurring [Member] | Measurement Input, Liquidity Premium | States and political subdivisions | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Maximum
Quantitative information about Level 3 fair value measurements
Liquidity Premium (as a percent)	1.30%	2.40%
Fair Value, Measurements, Recurring [Member] | Measurement Input, Liquidity Premium | States and political subdivisions | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Weighted Average [Member]
Quantitative information about Level 3 fair value measurements
Debt Securities, Measurement Input	0.5	0.6

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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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Value of input used to measure 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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-Publisher FASB
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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Value of input used to measure servicing asset.

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