Loans and Allowance for Credit Losses - Rollforward of Allowance for Credit/Loan Losses by Portfolio Segment (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	$ 229,979	$ 212,850	$ 222,996	$ 194,243
Charge-offs	(3,858)	(2,498)	(9,335)	(8,332)
Recoveries	1,002	2,637	3,462	3,828
Provision	15,000	12,000	25,000	35,250
Ending balance - ACL	242,123	224,989	242,123	224,989
Beginning balance - ACL on off-balance sheet	5,088	3,088	5,088	3,088
Provision	(950)	1,000	(950)	1,000
Ending balance - ACL on off-balance sheet	4,138	4,088	4,138	4,088
Commercial and Industrial Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	139,824	154,484	155,658	136,737
Charge-offs	(50)		(994)	(2,819)
Recoveries	366	2,098	1,618	2,886
Provision	10,386	7,228	(5,756)	27,006
Ending balance - ACL	150,526	163,810	150,526	163,810
Beginning balance - ACL on off-balance sheet	4,092	2,178	4,092	2,178
Provision	(1,887)	901	(1,887)	901
Ending balance - ACL on off-balance sheet	2,205	3,079	2,205	3,079
Specialty Lending Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance		922
Recoveries	1		2	1
Provision	(1)	(922)	(2)	(1)
Beginning balance - ACL on off-balance sheet	186	186	186	186
Provision	(186)		(186)
Ending balance - ACL on off-balance sheet		186		186
Commercial Real Estate Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	66,291	40,514	45,507	39,370
Charge-offs			(250)	(21)
Recoveries		21		21
Provision	2,571	1,657	23,605	2,822
Ending balance - ACL	68,862	42,192	68,862	42,192
Beginning balance - ACL on off-balance sheet	460	418	460	418
Provision	1,221	12	1,221	12
Ending balance - ACL on off-balance sheet	1,681	430	1,681	430
Consumer Real Estate Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	3,399	5,616	6,941	6,148
Charge-offs	(2)	(21)	(176)	(1,142)
Recoveries	4	5	610	18
Provision	166	927	(3,808)	1,503
Ending balance - ACL	3,567	6,527	3,567	6,527
Beginning balance - ACL on off-balance sheet	117	124	117	124
Provision	(37)	(5)	(37)	(5)
Ending balance - ACL on off-balance sheet	80	119	80	119
Consumer Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	531	453	1,089	494
Charge-offs	(261)	(411)	(669)	(680)
Recoveries	22	100	98	122
Provision	340	275	114	481
Ending balance - ACL	632	417	632	417
Beginning balance - ACL on off-balance sheet	9	13	9	13
Provision	4	(1)	4	(1)
Ending balance - ACL on off-balance sheet	13	12	13	12
Credit Cards Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	14,557	6,471	7,935	6,866
Charge-offs	(3,545)	(2,066)	(7,246)	(3,670)
Recoveries	609	413	1,134	780
Provision	2,315	2,413	12,113	3,255
Ending balance - ACL	13,936	7,231	13,936	7,231
Leases and Other Portfolio [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	1,557	2,049	2,608	2,221
Provision	87	(65)	(964)	(237)
Ending balance - ACL	1,644	1,984	1,644	1,984
Beginning balance - ACL on off-balance sheet	160	62	160	62
Provision	(45)	115	(45)	115
Ending balance - ACL on off-balance sheet	115	177	115	177
Total - Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	226,159	210,509	219,738	191,836
Charge-offs	(3,858)	(2,498)	(9,335)	(8,332)
Recoveries	1,002	2,637	3,462	3,828
Provision	15,864	11,513	25,302	34,829
Ending balance - ACL	239,167	222,161	239,167	222,161
Beginning balance - ACL on off-balance sheet	5,024	2,981	5,024	2,981
Provision	(930)	1,022	(930)	1,022
Ending balance - ACL on off-balance sheet	4,094	4,003	4,094	4,003
HTM [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	3,820	2,341	3,258	2,407
Provision	(864)	487	(302)	421
Ending balance - ACL	2,956	2,828	2,956	2,828
Beginning balance - ACL on off-balance sheet	64	107	64	107
Provision	(20)	(22)	(20)	(22)
Ending balance - ACL on off-balance sheet	$ 44	$ 85	$ 44	$ 85

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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