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Fair Value Measurements - Quantitative and Qualitative Information (Details) | Sep. 30, 2024 USD ($) | Dec. 31, 2023 USD ($)
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Quantitative information about Level 3 fair value measurements |  |
Mortgage servicing rights, fair value | $ 9,726,000 | $ 10,344,000
Securities available-for-sale, at fair value | 1,190,854,000 | 1,192,829,000
Fair Value, Inputs, Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Mortgage servicing rights, fair value | 9,726,000 | 10,344,000
Securities available-for-sale, at fair value | 16,168,000 | 15,329,000
Asset-backed Securities |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 63,947,000 | 68,436,000
States and political subdivisions |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 224,795,000 | 227,065,000
Collateralized mortgage obligations |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 384,271,000 | 392,544,000
Fair Value, Measurements, Recurring |  |
Quantitative information about Level 3 fair value measurements |  |
Mortgage servicing rights, fair value | 9,726,000 | 10,344,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Mortgage servicing rights, fair value | 9,726,000 | 10,344,000
Fair Value, Measurements, Recurring | Asset-backed Securities |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 63,947,000 | 68,436,000
Fair Value, Measurements, Recurring | Asset-backed Securities | Fair Value, Inputs, Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 3,300,000 | 2,270,000
Fair Value, Measurements, Recurring | States and political subdivisions |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 224,795,000 | 227,065,000
Fair Value, Measurements, Recurring | States and political subdivisions | Fair Value, Inputs, Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 12,868,000 | 13,059,000
Fair Value, Measurements, Recurring | Collateralized mortgage obligations |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 384,271,000 | 392,544,000
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | Asset-backed Securities | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | $ 3,300,000 | $ 2,270,000
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | Asset-backed Securities | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Minimum |  |
Quantitative information about Level 3 fair value measurements |  |
Debt Securities, Measurement Input | 0.049 | 0.056
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | Asset-backed Securities | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Maximum |  |
Quantitative information about Level 3 fair value measurements |  |
Debt Securities, Measurement Input | 0.049 | 0.056
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | Asset-backed Securities | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Weighted Average |  |
Quantitative information about Level 3 fair value measurements |  |
Debt Securities, Measurement Input | 0.049 | 0.056
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | Mortgage Servicing Rights | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Mortgage servicing rights, fair value | $ 9,726,000 | $ 10,344,000
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | Mortgage Servicing Rights | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Minimum |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 0.090 | 0.090
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | Mortgage Servicing Rights | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Maximum |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 0.110 | 0.110
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | Mortgage Servicing Rights | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Weighted Average |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 0.090 | 0.090
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | States and political subdivisions | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | $ 12,868,000 | $ 13,059,000
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | States and political subdivisions | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Minimum |  |
Quantitative information about Level 3 fair value measurements |  |
Debt Securities, Measurement Input | 0.052 | 0.032
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | States and political subdivisions | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Maximum |  |
Quantitative information about Level 3 fair value measurements |  |
Debt Securities, Measurement Input | 0.061 | 0.054
Fair Value, Measurements, Recurring | Measurement Input, Discount Rate | States and political subdivisions | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Weighted Average |  |
Quantitative information about Level 3 fair value measurements |  |
Debt Securities, Measurement Input | 0.061 | 0.047
Fair Value, Measurements, Recurring | Measurement Input, Constant Prepayment Rate | Mortgage Servicing Rights | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Minimum |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 0.000 | 0.051
Fair Value, Measurements, Recurring | Measurement Input, Constant Prepayment Rate | Mortgage Servicing Rights | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Maximum |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 0.381 | 0.330
Fair Value, Measurements, Recurring | Measurement Input, Constant Prepayment Rate | Mortgage Servicing Rights | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Weighted Average |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 0.073 | 0.066
Fair Value, Measurements, Recurring | Measurement Input, Liquidity Premium | States and political subdivisions | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Minimum |  |
Quantitative information about Level 3 fair value measurements |  |
Debt Securities, Measurement Input | 0.005 | 0.005
Fair Value, Measurements, Recurring | Measurement Input, Liquidity Premium | States and political subdivisions | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Maximum |  |
Quantitative information about Level 3 fair value measurements |  |
Debt Securities, Measurement Input | 0.005 | 0.005
Fair Value, Measurements, Recurring | Measurement Input, Liquidity Premium | States and political subdivisions | Discounted Cash Flow Valuation Technique | Fair Value, Inputs, Level 3 | Weighted Average |  |
Quantitative information about Level 3 fair value measurements |  |
Debt Securities, Measurement Input | 0.005 | 0.005

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- 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 + Details
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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 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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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 + Details
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