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Fair Value Measurements - Quantitative and Qualitative Information (Details) $ in Thousands	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	$ 11,041	$ 11,189
Securities available-for-sale, at fair value	1,335,622	1,539,359
Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	11,041	11,189
Securities available-for-sale, at fair value	14,938	36,011
Asset-backed Securities
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	134,319	201,928
States and political subdivisions
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	229,534	226,128
Collateralized mortgage obligations
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	407,495	533,768
Fair Value, Measurements, Recurring [Member]
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	11,041	11,189
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	11,041	11,189
Fair Value, Measurements, Recurring [Member] | Asset-backed Securities
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	134,319	201,928
Fair Value, Measurements, Recurring [Member] | Asset-backed Securities | Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value		15,012
Fair Value, Measurements, Recurring [Member] | States and political subdivisions
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	229,534	226,128
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	14,938	14,229
Fair Value, Measurements, Recurring [Member] | Collateralized mortgage obligations
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	407,495	533,768
Fair Value, Measurements, Recurring [Member] | Collateralized mortgage obligations | Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value		6,770
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Asset-backed Securities | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value		$ 15,012
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Asset-backed Securities | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Minimum
Quantitative information about Level 3 fair value measurements
Debt Securities, Measurement Input		0.062
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Asset-backed Securities | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Maximum
Quantitative information about Level 3 fair value measurements
Debt Securities, Measurement Input		0.065
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Asset-backed Securities | 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		0.063
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]
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	$ 11,041	$ 11,189
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		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] | 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] | 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	0.090	0.090
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]
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	$ 14,938	$ 14,229
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	0.090
Debt Securities, Measurement Input	0.031	0.023
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	0.110
Debt Securities, Measurement Input	0.052	0.058
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	0.045	0.044
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Collateralized mortgage obligations | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value		$ 6,770
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Collateralized mortgage obligations | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Minimum
Quantitative information about Level 3 fair value measurements
Debt Securities, Measurement Input		0.070
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Collateralized mortgage obligations | Discounted Cash Flow Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Maximum
Quantitative information about Level 3 fair value measurements
Debt Securities, Measurement Input		0.070
Fair Value, Measurements, Recurring [Member] | Measurement Input, Discount Rate | Collateralized mortgage obligations | 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		0.070
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	0.030	0.036
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	0.223	0.273
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	0.063	0.062
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
Debt Securities, Measurement Input	0.003	0.003
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
Debt Securities, Measurement Input	0.005	0.005
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	0.005	0.005

X

- Definition

Amount excluding accrued interest, 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/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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+ References

No definition available.

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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
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481260/860-50-45-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481260/860-50-45-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481260/860-50-45-2

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Value of input used to measure servicing asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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