Loans and the Allowance for Credit Losses - Recorded Investment in Non-Accrual Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Impaired [Line Items]
Non-accrual loans	$ 26,808	$ 38,185
Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	1,841	2,946
Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	4,777	5,044
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	9,557	16,366
Commercial Real Estate [Member] | Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans		112
Commercial Real Estate [Member] | Commercial Real Estate - Improved Property [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	9,557	16,254
Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	10,582	13,695
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	$ 51	$ 134