Income Taxes - Company's Net Deferred Tax Asset Recorded in Other Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Allowance for losses and reserve for unfunded commitments	$ 32,519	$ 26,361
Deferred compensation	1,696	1,758
Other accrued expenses	2,720	1,994
Additional unfunded status of the supplemental retirement plans	16,036	13,693
Operating lease liability	8,575	7,769
State taxes	3,649	3,251
Share based compensation	1,132	952
Nonaccrual interest	643	937
Acquisition cost basis	14,640	506
Unrealized loss on securities	85,897	116
Tax credits	852	513
Net operating loss carryforwards	2,098	1,131
Other	120	813
Total deferred tax assets	170,577	59,794
Deferred tax liabilities:
Securities income	(777)	(762)
Depreciation	(8,270)	(6,198)
Right of use asset	(7,941)	(7,588)
Funded pension liability	(4,110)	(709)
Securities accretion	(1,265)	(846)
Mortgage servicing rights valuation	(1,976)	(1,726)
Core deposit intangible	(4,778)	(3,248)
Junior subordinated debt	(1,293)	(1,422)
Prepaid expenses and other	(991)	(488)
Total deferred tax liability	(31,401)	(22,987)
Net deferred tax asset	$ 139,176	$ 36,807