Loans and Allowance for Credit Losses - Summary of Loan Classes and Aging of Past Due Loans (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 22,483,542	$ 21,031,189
Nonaccrual Loans	19,347	19,269
30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	12,202	8,775
Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	10,675	1,617
Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	42,224	29,661
Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	22,441,318	21,001,528
Commercial and Industrial Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	9,901,347	9,205,986
Nonaccrual Loans	11,412	11,356
Commercial and Industrial Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	4,257	2,456
Commercial and Industrial Portfolio [Member] | Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	6,029	2
Commercial and Industrial Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	21,698	13,814
Commercial and Industrial Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	9,879,649	9,192,172
Specialty Lending Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	561,216	602,706
Specialty Lending Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	561,216	602,706
Commercial Real Estate Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	8,268,217	7,616,086
Nonaccrual Loans	2,367	2,505
Commercial Real Estate Portfolio Segment | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	980	2,167
Commercial Real Estate Portfolio Segment | Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	1,887	191
Commercial Real Estate Portfolio Segment | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	5,234	4,863
Commercial Real Estate Portfolio Segment | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	8,262,983	7,611,223
Consumer Real Estate Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,918,426	2,723,269
Nonaccrual Loans	5,146	4,882
Consumer Real Estate Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	154	10
Consumer Real Estate Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	5,300	4,892
Consumer Real Estate Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,913,126	2,718,377
Consumer Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	131,292	145,666
Nonaccrual Loans	38	61
Consumer Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	75	613
Consumer Portfolio [Member] | Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	14	20
Consumer Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	127	694
Consumer Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	131,165	144,972
Credit Cards Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	445,152	431,672
Nonaccrual Loans	384	441
Credit Cards Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	6,736	3,529
Credit Cards Portfolio [Member] | Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,745	1,404
Credit Cards Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	9,865	5,374
Credit Cards Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	435,287	426,298
Leases and Other Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	257,892	305,804
Nonaccrual Loans		24
Leases and Other Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans		24
Leases and Other Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 257,892	$ 305,780