Fair Value Measurements - Summary of Financial Instruments Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Assets
Securities available-for-sale	$ 2,351,493	$ 1,862,270
Estimate of Fair Value Measurement
Assets
Other investments	91,042	69,801
Obligations of U.S. Government-sponsored enterprises
Assets
Securities available-for-sale	244,506	276,040
Obligations of states and political subdivisions
Assets
Securities available-for-sale	524,746	409,197
Agency mortgage-backed securities
Assets
Securities available-for-sale	1,444,552	1,027,394
U.S. Treasury bills
Assets
Securities available-for-sale	114,041	128,893
Corporate debt securities
Assets
Securities available-for-sale	23,648	20,746
Recurring basis | Estimate of Fair Value Measurement
Assets
Securities available-for-sale	2,351,493	1,862,270
Other investments	3,085	2,983
Derivative financial instruments	13,279	15,144
Total assets	2,367,857	1,880,397
Liabilities
Derivative financial instruments	10,552	18,692
Total liabilities	10,552	18,692
Recurring basis | Obligations of U.S. Government-sponsored enterprises | Estimate of Fair Value Measurement
Assets
Securities available-for-sale	244,506	276,040
Recurring basis | Obligations of states and political subdivisions | Estimate of Fair Value Measurement
Assets
Securities available-for-sale	524,746	409,197
Recurring basis | Agency mortgage-backed securities | Estimate of Fair Value Measurement
Assets
Securities available-for-sale	1,444,552	1,027,394
Recurring basis | U.S. Treasury bills | Estimate of Fair Value Measurement
Assets
Securities available-for-sale	23,648	128,893
Recurring basis | Corporate debt securities | Estimate of Fair Value Measurement
Assets
Securities available-for-sale	114,041	20,746
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Securities available-for-sale	0	0
Other investments	0	0
Derivative financial instruments	0	0
Total assets	0	0
Liabilities
Derivative financial instruments	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	2,351,493	1,862,270
Other investments	3,085	2,983
Derivative financial instruments	13,279	15,144
Total assets	2,367,857	1,880,397
Liabilities
Derivative financial instruments	10,552	18,692
Total liabilities	10,552	18,692
Recurring basis | Significant Other Observable Inputs (Level 2) | Obligations of U.S. Government-sponsored enterprises
Assets
Securities available-for-sale	244,506	276,040
Recurring basis | Significant Other Observable Inputs (Level 2) | Obligations of states and political subdivisions
Assets
Securities available-for-sale	524,746	409,197
Recurring basis | Significant Other Observable Inputs (Level 2) | Agency mortgage-backed securities
Assets
Securities available-for-sale	1,444,552	1,027,394
Recurring basis | Significant Other Observable Inputs (Level 2) | U.S. Treasury bills
Assets
Securities available-for-sale	23,648	128,893
Recurring basis | Significant Other Observable Inputs (Level 2) | Corporate debt securities
Assets
Securities available-for-sale	114,041	20,746
Recurring basis | Significant Unobservable Inputs (Level 3)
Assets
Securities available-for-sale	0	0
Other investments	0	0
Derivative financial instruments	0	0
Total assets	0	0
Liabilities
Derivative financial instruments	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