Loans and Allowance for Credit Losses - Summary of Loan Classes and Aging of Past Due Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 23,637,649	$ 23,172,484
Nonaccrual Loans	17,756	13,212
30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	15,409	11,283
Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	3,076	3,111
Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	36,241	27,606
Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	23,601,408	23,144,878
Commercial and Industrial Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	9,940,487	9,929,929
Nonaccrual Loans	5,634	7,033
Commercial and Industrial Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,869	2,851
Commercial and Industrial Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	8,503	9,884
Commercial and Industrial Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	9,931,984	9,920,045
Specialty Lending Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	508,162	498,786
Specialty Lending Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	508,162	498,786
Commercial Real Estate Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	9,285,165	8,893,926
Nonaccrual Loans	5,831	737
Commercial Real Estate Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	1,901	1,848
Commercial Real Estate Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	7,732	2,585
Commercial Real Estate Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	9,277,433	8,891,341
Consumer Real Estate Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,972,731	2,960,632
Nonaccrual Loans	5,994	5,058
Consumer Real Estate Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,405	1,137
Consumer Real Estate Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	8,399	6,195
Consumer Real Estate Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,964,332	2,954,437
Consumer Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	146,602	163,291
Nonaccrual Loans	29	28
Consumer Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	73	104
Consumer Portfolio [Member] | Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	21	55
Consumer Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	123	187
Consumer Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	146,479	163,104
Credit Cards Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	538,498	423,956
Nonaccrual Loans	268	285
Credit Cards Portfolio [Member] | 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	8,161	5,343
Credit Cards Portfolio [Member] | Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	3,055	3,056
Credit Cards Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	11,484	8,684
Credit Cards Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	527,014	415,272
Leases and Other Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	246,004	301,964
Nonaccrual Loans		71
Leases and Other Portfolio [Member] | Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans		71
Leases and Other Portfolio [Member] | Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 246,004	$ 301,893