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, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income Tax Disclosure [Abstract]
Provision at statutory rate of 21%	$ 29,389	$ 16,117	$ 21,766	$ 38,051
Tax-exempt income:
Tax-exempt interest	(3,413)	(2,762)	(6,406)	(5,541)
Section 291/265 interest disallowance	38	30	66	63
Company-owned life insurance income	(938)	(556)	(1,656)	(1,099)
Tax-exempt income	(4,313)	(3,288)	(7,996)	(6,577)
State income taxes	4,085	2,200	758	5,173
Interim period effective rate adjustment	(3,967)	(662)	3,073	(2,437)
Tax credit investments - federal	(1,292)	(1,430)	(2,561)	(2,523)
Other, net	1,062	1,023	1,210	(97)
Income tax expense (benefit)	$ 24,964	$ 13,960	$ 16,250	$ 31,590
Effective tax rate	17.80%	18.20%	15.70%	17.40%

Effective Income Tax Rate Reconciliation, Tax Exempt Income, Life Insurance, Amount

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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