Fair Value Measurements - Quantitative and Qualitative Information (Details)	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Quantitative information about Level 3 fair value measurements
Fair Value	$ 1,177,688,000	$ 1,161,701,000
Mortgage servicing rights, fair value	9,680,000	10,374,000
Fair Value, Inputs, Level 3
Quantitative information about Level 3 fair value measurements
Fair Value	14,541,000	15,150,000
Mortgage servicing rights, fair value	9,680,000
States and political subdivisions
Quantitative information about Level 3 fair value measurements
Fair Value	208,814,000	215,456,000
Asset-backed Securities
Quantitative information about Level 3 fair value measurements
Fair Value	48,119,000	62,303,000
Fair Value, Measurements, Recurring
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	9,680,000	10,374,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	9,680,000	10,374,000
Fair Value, Measurements, Recurring \| States and political subdivisions
Quantitative information about Level 3 fair value measurements
Fair Value	208,814,000	215,456,000
Fair Value, Measurements, Recurring \| States and political subdivisions \| Fair Value, Inputs, Level 3
Quantitative information about Level 3 fair value measurements
Fair Value	11,106,000	11,896,000
Fair Value, Measurements, Recurring \| Asset-backed Securities
Quantitative information about Level 3 fair value measurements
Fair Value	48,119,000	62,303,000
Fair Value, Measurements, Recurring \| Asset-backed Securities \| Fair Value, Inputs, Level 3
Quantitative information about Level 3 fair value measurements
Fair Value	3,435,000	3,254,000
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
Fair Value	$ 11,106,000	$ 11,896,000
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	0.036	0.053
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	0.051	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	0.041	0.054
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
Fair Value	$ 3,435,000	$ 3,254,000
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	0.052	0.049
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	0.052	0.049
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	0.052	0.049
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	$ 9,680,000	$ 10,374,000
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	0.09	0.09
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	0.11	0.11
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	0.09	0.09
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
Fair Value, Measurements, Recurring \| Measurement Input, 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	0.044	0
Fair Value, Measurements, Recurring \| Measurement Input, 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	0.367	0.315
Fair Value, Measurements, Recurring \| Measurement Input, 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	0.074	0.069

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).

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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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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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