Loans and Allowance for Loan Losses - Summary Pertaining to the Breakdown of the Company's Nonaccrual Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Disclosure Detail Of Non Accrual Loans [Line Items]
Total non-accrual loans	$ 32,993	$ 41,005
Commercial and industrial | Commercial Portfolio Segment
Disclosure Detail Of Non Accrual Loans [Line Items]
Total non-accrual loans	12,400	11,714
Commercial real estate | Commercial Portfolio Segment
Disclosure Detail Of Non Accrual Loans [Line Items]
Total non-accrual loans	0	915
Commercial construction | Commercial Portfolio Segment
Disclosure Detail Of Non Accrual Loans [Line Items]
Total non-accrual loans	0	0
Business banking | Commercial Portfolio Segment
Disclosure Detail Of Non Accrual Loans [Line Items]
Total non-accrual loans	8,230	17,430
Residential real estate | Residential Portfolio Segment
Disclosure Detail Of Non Accrual Loans [Line Items]
Total non-accrual loans	6,681	6,815
Consumer home equity | Consumer Portfolio Segment
Disclosure Detail Of Non Accrual Loans [Line Items]
Total non-accrual loans	4,732	3,602
Other consumer | Consumer Portfolio Segment
Disclosure Detail Of Non Accrual Loans [Line Items]
Total non-accrual loans	$ 950	$ 529