Loans and the Allowance for Credit Losses - Summary of Changes in Allowance for Credit Losses (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses - loans, beginning balance	$ 138,766	$ 130,675
Allowance for credit losses - loan commitments, beginning balance	6,120	8,604
Total beginning allowance for credit losses - loans and loan commitments	144,886	139,279
Initial allowance for credit losses on acquired PCD loans	20,179
Provision for loan losses	72,021	13,991
Provision for loan commitments	48	590
Total provision for credit losses - loans and loan commitments	72,069	14,581
Charge-offs	(10,375)	(11,226)
Recoveries	3,275	3,069
Net (charge-offs) recoveries	(7,100)	(8,157)
Allowance for credit losses - loans, ending balance	223,866	136,509
Allowance for credit losses - loan commitments, ending balance	6,168	9,194
Total ending allowance for credit losses - loans and loan commitments	230,034	145,703
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses - loans, beginning balance	42,398	36,644
Allowance for credit losses - loan commitments, beginning balance		429
Total beginning allowance for credit losses - loans and loan commitments	42,398	37,073
Initial allowance for credit losses on acquired PCD loans	7,160
Provision for loan losses	16,833	9,726
Provision for loan commitments		(429)
Total provision for credit losses - loans and loan commitments	16,833	9,297
Charge-offs	(3,821)	(6,072)
Recoveries	1,367	1,107
Net (charge-offs) recoveries	(2,454)	(4,965)
Allowance for credit losses - loans, ending balance	63,937	41,405
Total ending allowance for credit losses - loans and loan commitments	63,937	41,405
Deposit Overdraft [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses - loans, beginning balance	1,713	1,366
Total beginning allowance for credit losses - loans and loan commitments	1,713	1,366
Provision for loan losses	1,664	833
Total provision for credit losses - loans and loan commitments	1,664	833
Charge-offs	(1,364)	(861)
Recoveries	308	213
Net (charge-offs) recoveries	(1,056)	(648)
Allowance for credit losses - loans, ending balance	2,321	1,551
Total ending allowance for credit losses - loans and loan commitments	2,321	1,551
Commercial Real Estate [Member] | Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses - loans, beginning balance	8,411	7,123
Allowance for credit losses - loan commitments, beginning balance	5,105	6,894
Total beginning allowance for credit losses - loans and loan commitments	13,516	14,017
Initial allowance for credit losses on acquired PCD loans	177
Provision for loan losses	2,317	1,516
Provision for loan commitments	254	1,046
Total provision for credit losses - loans and loan commitments	2,571	2,562
Charge-offs		(813)
Recoveries	11
Net (charge-offs) recoveries	11	(813)
Allowance for credit losses - loans, ending balance	10,916	7,826
Allowance for credit losses - loan commitments, ending balance	5,359	7,940
Total ending allowance for credit losses - loans and loan commitments	16,275	15,766
Commercial Real Estate [Member] | Commercial Real Estate - Improved Property [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses - loans, beginning balance	59,828	59,351
Total beginning allowance for credit losses - loans and loan commitments	59,828	59,351
Initial allowance for credit losses on acquired PCD loans	5,951
Provision for loan losses	34,027	(402)
Total provision for credit losses - loans and loan commitments	34,027	(402)
Charge-offs	(678)	(815)
Recoveries	116	443
Net (charge-offs) recoveries	(562)	(372)
Allowance for credit losses - loans, ending balance	99,244	58,577
Total ending allowance for credit losses - loans and loan commitments	99,244	58,577
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses - loans, beginning balance	21,790	21,218
Allowance for credit losses - loan commitments, beginning balance	1,015	1,276
Total beginning allowance for credit losses - loans and loan commitments	22,805	22,494
Initial allowance for credit losses on acquired PCD loans	3,192
Provision for loan losses	9,745	1,342
Provision for loan commitments	(206)	(22)
Total provision for credit losses - loans and loan commitments	9,539	1,320
Charge-offs	(412)	(272)
Recoveries	199	115
Net (charge-offs) recoveries	(213)	(157)
Allowance for credit losses - loans, ending balance	34,514	22,403
Allowance for credit losses - loan commitments, ending balance	809	1,254
Total ending allowance for credit losses - loans and loan commitments	35,323	23,657
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses - loans, beginning balance	3,391	3,956
Total beginning allowance for credit losses - loans and loan commitments	3,391	3,956
Initial allowance for credit losses on acquired PCD loans	3,095
Provision for loan losses	6,476	773
Total provision for credit losses - loans and loan commitments	6,476	773
Charge-offs	(3,283)	(1,980)
Recoveries	1,038	894
Net (charge-offs) recoveries	(2,245)	(1,086)
Allowance for credit losses - loans, ending balance	10,717	3,643
Total ending allowance for credit losses - loans and loan commitments	10,717	3,643
Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses - loans, beginning balance	1,235	1,017
Allowance for credit losses - loan commitments, beginning balance		5
Total beginning allowance for credit losses - loans and loan commitments	1,235	1,022
Initial allowance for credit losses on acquired PCD loans	604
Provision for loan losses	959	203
Provision for loan commitments		(5)
Total provision for credit losses - loans and loan commitments	959	198
Charge-offs	(817)	(413)
Recoveries	236	297
Net (charge-offs) recoveries	(581)	(116)
Allowance for credit losses - loans, ending balance	2,217	1,104
Total ending allowance for credit losses - loans and loan commitments	$ 2,217	$ 1,104