Loans and Allowance for Credit Losses - Summary of Loan Classes and Aging of Past Due Loans (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 19,883,573	$ 17,170,871
Nonaccrual Loans	19,817	92,300
30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	13,201	6,509
Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,513	2,633
Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	35,531	101,442
Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	19,848,042	17,069,429
Commercial and Industrial Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	8,789,114	7,258,120
Nonaccrual Loans	11,386	82,845
Commercial and Industrial Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	6,479	2,827
Commercial and Industrial Portfolio [Member] | Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	425	896
Commercial and Industrial Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	18,290	86,568
Commercial and Industrial Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	8,770,824	7,171,552
Specialty Lending Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	548,123	522,362
Specialty Lending Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	548,123	522,362
Commercial Real Estate Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	7,104,217	6,267,544
Nonaccrual Loans	2,596	4,688
Commercial Real Estate Portfolio Segment | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	4,069	962
Commercial Real Estate Portfolio Segment | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	6,665	5,650
Commercial Real Estate Portfolio Segment | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	7,097,552	6,261,894
Consumer Real Estate Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,634,518	2,320,033
Nonaccrual Loans	4,902	4,210
Consumer Real Estate Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	346	246
Consumer Real Estate Portfolio [Member] | Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans		489
Consumer Real Estate Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	5,248	4,945
Consumer Real Estate Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,629,270	2,315,088
Consumer Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	134,825	129,135
Nonaccrual Loans	553	75
Consumer Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	107	105
Consumer Portfolio [Member] | Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	1	2
Consumer Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	661	182
Consumer Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	134,164	128,953
Credit Cards Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	435,980	391,389
Nonaccrual Loans	356	457
Credit Cards Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,200	2,369
Credit Cards Portfolio [Member] | Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,087	1,246
Credit Cards Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	4,643	4,072
Credit Cards Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	431,337	387,317
Leases and Other Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	236,796	282,288
Nonaccrual Loans	24	25
Leases and Other Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	24	25
Leases and Other Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 236,772	$ 282,263