Loans and the Allowance for Credit Losses - Schedule of Recorded Investment in Loans by Category (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	$ 10,277,662	$ 9,733,478
Loans held for sale	12,887	25,277
Total loans	10,290,549	9,758,755
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	1,503,848	1,427,645
Commercial And Industrial - PPP [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	13,008	162,675
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	5,831,384	5,538,968
Commercial Real Estate [Member] | Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	955,644	833,880
Commercial Real Estate [Member] | Commercial Real Estate - Improved Property [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	4,875,740	4,705,088
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	2,010,344	1,721,378
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	309,313	277,130
Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	$ 609,765	$ 605,682