Fair Value Measurements - Summary of Financial Instruments Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Assets
Securities available for sale	$ 1,555,109	$ 1,535,807
Estimate of Fair Value Measurement
Assets
Other investments	60,173	61,123
Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	265,705	237,785
Obligations of states and political subdivisions
Assets
Securities available for sale	430,693	417,444
Agency mortgage-backed securities
Assets
Securities available for sale	650,451	659,404
U.S. Treasury bills
Assets
Securities available for sale	200,103	208,534
Corporate debt securities
Assets
Securities available for sale	8,157	12,640
Recurring basis \| Estimate of Fair Value Measurement
Assets
Securities available for sale	1,555,109	1,535,807
Other investments	2,770	2,667
Derivatives	19,975	22,958
Total assets	1,577,854	1,561,432
Liabilities
Derivatives	16,858	21,581
Total liabilities	16,858	21,581
Recurring basis \| Obligations of U.S. Government-sponsored enterprises \| Estimate of Fair Value Measurement
Assets
Securities available for sale	265,705	237,785
Recurring basis \| Obligations of states and political subdivisions \| Estimate of Fair Value Measurement
Assets
Securities available for sale	430,693	417,444
Recurring basis \| Agency mortgage-backed securities \| Estimate of Fair Value Measurement
Assets
Securities available for sale	650,451	659,404
Recurring basis \| U.S. Treasury bills \| Estimate of Fair Value Measurement
Assets
Securities available for sale	200,103	208,534
Recurring basis \| Corporate debt securities \| Estimate of Fair Value Measurement
Assets
Securities available for sale	8,157	12,640
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Securities available for sale	0	0
Other investments	0	0
Derivatives	0	0
Total assets	0	0
Liabilities
Derivatives	0	0
Total liabilities	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Obligations of states and political subdivisions
Assets
Securities available for sale	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Agency mortgage-backed securities
Assets
Securities available for sale	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. Treasury bills
Assets
Securities available for sale	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Corporate debt securities
Assets
Securities available for sale	0	0
Recurring basis \| Significant Other Observable Inputs (Level 2)
Assets
Securities available for sale	1,555,109	1,535,807
Other investments	2,770	2,667
Derivatives	19,975	22,958
Total assets	1,577,854	1,561,432
Liabilities
Derivatives	16,858	21,581
Total liabilities	16,858	21,581
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	265,705	237,785
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Obligations of states and political subdivisions
Assets
Securities available for sale	430,693	417,444
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Agency mortgage-backed securities
Assets
Securities available for sale	650,451	659,404
Recurring basis \| Significant Other Observable Inputs (Level 2) \| U.S. Treasury bills
Assets
Securities available for sale	200,103	208,534
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Corporate debt securities
Assets
Securities available for sale	8,157	12,640
Recurring basis \| Significant Unobservable Inputs (Level 3)
Assets
Securities available for sale	0	0
Other investments	0	0
Derivatives	0	0
Total assets	0	0
Liabilities
Derivatives	0	0
Total liabilities	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Obligations of states and political subdivisions
Assets
Securities available for sale	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Agency mortgage-backed securities
Assets
Securities available for sale	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| U.S. Treasury bills
Assets
Securities available for sale	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Corporate debt securities
Assets
Securities available for sale	$ 0	$ 0

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount 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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Fair value of financial and nonfinancial obligations.

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