Loans and Allowance for Credit Losses - Summary of Loan Classes and Aging of Past Due Loans (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 18,972,158	$ 17,170,871
Nonaccrual Loans	18,117	92,300
30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	20,123	6,509
Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	3,446	2,633
Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	41,686	101,442
Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	18,930,472	17,069,429
Commercial and Industrial Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	8,308,854	7,258,120
Nonaccrual Loans	10,158	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	15,369	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	1,747	896
Commercial and Industrial Portfolio [Member] \| Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	27,274	86,568
Commercial and Industrial Portfolio [Member] \| Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	8,281,580	7,171,552
Specialty Lending Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	545,837	522,362
Specialty Lending Portfolio [Member] \| Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	545,837	522,362
Commercial Real Estate Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	6,725,833	6,267,544
Nonaccrual Loans	2,600	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	1,776	962
Commercial Real Estate Portfolio Segment \| Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	100
Commercial Real Estate Portfolio Segment \| Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	4,476	5,650
Commercial Real Estate Portfolio Segment \| Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	6,721,357	6,261,894
Consumer Real Estate Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,528,892	2,320,033
Nonaccrual Loans	4,437	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	176	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	4,613	4,945
Consumer Real Estate Portfolio [Member] \| Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,524,279	2,315,088
Consumer Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	172,591	129,135
Nonaccrual Loans	561	75
Consumer Portfolio [Member] \| 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	121	105
Consumer Portfolio [Member] \| Greater than 90 days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans		2
Consumer Portfolio [Member] \| Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	682	182
Consumer Portfolio [Member] \| Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	171,909	128,953
Credit Cards Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	397,292	391,389
Nonaccrual Loans	336	457
Credit Cards Portfolio [Member] \| 30-89 Days Past Due and Accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	2,681	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	1,599	1,246
Credit Cards Portfolio [Member] \| Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	4,616	4,072
Credit Cards Portfolio [Member] \| Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	392,676	387,317
Leases and Other Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	292,859	282,288
Nonaccrual Loans	25	25
Leases and Other Portfolio [Member] \| Total Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	25	25
Leases and Other Portfolio [Member] \| Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 292,834	$ 282,263