Fair Value Measurements - Summary of Financial Instruments Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets
Securities available for sale	$ 1,392,444	$ 1,366,006
Estimate of Fair Value Measurement [Member]
Assets
Other investments	57,601	56,884
Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	235,584	173,511
Obligations of states and political subdivisions
Assets
Securities available for sale	449,358	575,084
Agency mortgage-backed securities
Assets
Securities available for sale	580,196	513,859
U.S. Treasury bills
Assets
Securities available for sale	115,581	91,170
Corporate debt securities
Assets
Securities available for sale	11,725	12,382
Recurring basis \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	1,392,444	1,366,006
Other investments	2,843	3,012
Derivatives	7,771	12,869
Total assets	1,403,058	1,381,887
Liabilities
Derivatives	7,990	15,794
Total liabilities	7,990	15,794
Recurring basis \| Obligations of U.S. Government-sponsored enterprises \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	235,584	173,511
Recurring basis \| Obligations of states and political subdivisions \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	449,358	575,084
Recurring basis \| Agency mortgage-backed securities \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	580,196	513,859
Recurring basis \| U.S. Treasury bills \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	115,581	91,170
Recurring basis \| Corporate debt securities \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	11,725	12,382
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	1,392,444	1,366,006
Other investments	2,843	3,012
Derivatives	7,771	12,869
Total assets	1,403,058	1,381,887
Liabilities
Derivatives	7,990	15,794
Total liabilities	7,990	15,794
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	235,584	173,511
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Obligations of states and political subdivisions
Assets
Securities available for sale	449,358	575,084
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Agency mortgage-backed securities
Assets
Securities available for sale	580,196	513,859
Recurring basis \| Significant Other Observable Inputs (Level 2) \| U.S. Treasury bills
Assets
Securities available for sale	115,581	91,170
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Corporate debt securities
Assets
Securities available for sale	11,725	12,382
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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