Discontinued Operations - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Oct. 31, 2023	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 19, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total noninterest expense		$ 109,869	$ 99,934	$ 211,071	$ 195,825
Discontinued Operations, Held-for-Sale | Insurance Agency Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross cash consideration						$ 515,000
Net cash consideration	$ 498,100
Working capital adjustment	4,200
Transaction expenses	17,000
Post-retirement liabilities	4,100
Fiduciary cash transferred	7,400
Gain on disposition of assets	408,600
Total noninterest expense	$ 22,300
Disposal Group, Not Discontinued Operations, Transferrable Upon Sale to Entity | Insurance Agency Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Transitional services period	6 months