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Fair Value Measurements - Quantitative and Qualitative Information (Details) $ in Thousands	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Mar. 31, 2021 USD ($)
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	$ 10,376	$ 7,097
Securities available-for-sale, at fair value	1,816,450	1,692,488
Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	10,376	7,097
Securities available-for-sale, at fair value	13,833	14,092
States and political subdivisions
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	236,408	256,465
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	13,800		$ 4,600
Collateralized mortgage obligations
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	696,513	672,967
Fair Value, Measurements, Recurring [Member]
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	10,376	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	10,376	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	236,408	256,465
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	13,833	14,092
Fair Value, Measurements, Recurring [Member] | Collateralized mortgage obligations
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	$ 696,513	$ 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	9.0	11.0
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	11.0	15.0
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	9.0	11.0
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	5.7	0.0
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	28.9	36.6
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	6.2	11.9

X

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-Subparagraph (b)
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Value of input used to measure servicing asset.

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-Name Accounting Standards Codification
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