Federal and State Income Taxes - Deferred Tax Assets and Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets
Available-for-sale debt securities	$ 124,533	$ 157,381
Allowance for credit losses	53,074	52,445
Operating lease liabilities	11,093	11,871
Employee benefits	9,465	11,024
Deferred compensation	8,690	8,211
Interest rate swaps	4,502	0
Acquisition fair market value adjustments	3,606	4,932
Transferred debt securities	1,601	3,017
Net operating loss carryforwards	919	1,253
Other	4,112	2,376
Total gross deferred tax assets	221,595	252,510
Deferred tax liabilities
Depreciation of premises and equipment	(17,728)	(17,091)
Operating lease ROU assets	(10,207)	(11,004)
Deferred loan costs	(10,103)	(10,083)
Intangibles	(6,014)	(8,212)
Debt securities fair value hedge	(4,502)	0
Mortgage servicing rights	(3,137)	(3,408)
Other	(10,834)	(9,525)
Total gross deferred tax liabilities	(62,525)	(59,323)
Net deferred tax asset	$ 159,070	$ 193,187