Fair Value Measurements - Quantitative and Qualitative Information (Details) $ in Thousands	Sep. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Quantitative information about Level 3 fair value measurements
Fair Value	$ 1,157,480	$ 1,161,701
Mortgage servicing rights, fair value	9,549	10,374
Fair Value, Inputs, Level 3
Quantitative information about Level 3 fair value measurements
Fair Value	16,041	15,150
Mortgage servicing rights, fair value	9,549
States and political subdivisions
Quantitative information about Level 3 fair value measurements
Fair Value	210,675	215,456
Asset-backed Securities
Quantitative information about Level 3 fair value measurements
Fair Value	47,802	62,303
Fair Value, Measurements, Recurring
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	9,549	10,374
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	9,549	10,374
Fair Value, Measurements, Recurring \| States and political subdivisions
Quantitative information about Level 3 fair value measurements
Fair Value	210,675	215,456
Fair Value, Measurements, Recurring \| States and political subdivisions \| Fair Value, Inputs, Level 3
Quantitative information about Level 3 fair value measurements
Fair Value	11,441	11,896
Fair Value, Measurements, Recurring \| Asset-backed Securities
Quantitative information about Level 3 fair value measurements
Fair Value	47,802	62,303
Fair Value, Measurements, Recurring \| Asset-backed Securities \| Fair Value, Inputs, Level 3
Quantitative information about Level 3 fair value measurements
Fair Value	4,600	3,254
Fair Value, Measurements, Recurring \| 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	$ 11,441	$ 11,896
Fair Value, Measurements, Recurring \| 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	0.034	0.053
Fair Value, Measurements, Recurring \| 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	0.05	0.054
Fair Value, Measurements, Recurring \| 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 \| 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	$ 4,600	$ 3,254
Fair Value, Measurements, Recurring \| 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	0.051	0.049
Fair Value, Measurements, Recurring \| 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	0.051	0.049
Fair Value, Measurements, Recurring \| 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	0.051	0.049
Fair Value, Measurements, Recurring \| 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	$ 9,549	$ 10,374
Fair Value, Measurements, Recurring \| 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 \| 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 \| 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	0.105	0.09
Fair Value, Measurements, Recurring \| 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 \| 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 \| 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 \| Prepayment Speed \| 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	0.018	0
Fair Value, Measurements, Recurring \| Prepayment Speed \| 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	0.374	0.315
Fair Value, Measurements, Recurring \| Prepayment Speed \| 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	0.093	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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Value of input used to measure servicing asset.

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