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Income Taxes - Summary of Differences in Taxes from Continuing Operations Computed at Statutory Rate (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Income Tax Disclosure [Abstract]
Provision at statutory rate	$ 32,698	$ 32,861	$ 70,826	$ 64,943
Tax-exempt income:
Tax-exempt interest	(5,599)	(5,027)	(9,851)	(9,985)
Section 291/265 interest disallowance	1,364	957	2,033	1,841
Company-owned life insurance income	(1,397)	(1,178)	(2,532)	(1,872)
Tax-exempt income	(5,632)	(5,248)	(10,350)	(10,016)
State income taxes	5,094	6,333	11,995	11,480
Interim period effective rate adjustment	(159)	(70)	(306)	873
Tax credit investments - federal	(5,156)	(3,106)	(9,258)	(6,160)
Officer compensation limitation	1,436	1,491	1,808	2,256
Non-deductible FDIC premiums	2,816	2,032	4,853	3,779
Other, net	(799)	957	(2,366)	583
Income tax expense	$ 30,298	$ 35,250	$ 67,202	$ 67,738
Effective tax rate	19.50%	22.50%	19.90%	21.90%

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