Revenue Recognition - Summary of Disaggregation of Revenue According to Revenue Stream and Business Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Disaggregation Of Revenue [Line Items]
Revenue (Expense) out of Scope of ASC 606	$ 9,909	$ 4,509
Noninterest income	123,678	108,897
Trust and Securities Processing [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	59,528	54,834
Trading and Investment Banking [Member]
Disaggregation Of Revenue [Line Items]
Revenue (Expense) out of Scope of ASC 606	5,285	9,055
Noninterest income	5,440	9,356
Service Charges On Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue (Expense) out of Scope of ASC 606	70	70
Noninterest income	24,642	21,976
Insurance Fees and Commissions [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	259	420
Brokerage Fees [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	3,456	3,334
Bankcard Fees [Member]
Disaggregation Of Revenue [Line Items]
Revenue (Expense) out of Scope of ASC 606	(7,890)	(7,616)
Noninterest income	16,635	14,673
Investment Securities Losses, Net [Member]
Disaggregation Of Revenue [Line Items]
Revenue (Expense) out of Scope of ASC 606	(522)	(8,336)
Noninterest income	(522)	(8,336)
Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue (Expense) out of Scope of ASC 606	12,966	11,336
Noninterest income	14,240	12,640
Commercial Banking [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	23,116	20,735
Noninterest income	26,707	8,176
Commercial Banking [Member] \| Service Charges On Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	8,945	7,905
Commercial Banking [Member] \| Brokerage Fees [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	33	64
Commercial Banking [Member] \| Bankcard Fees [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	13,974	12,535
Commercial Banking [Member] \| Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	164	231
Institutional Banking [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	66,769	56,899
Noninterest income	73,262	68,421
Institutional Banking [Member] \| Trust and Securities Processing [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	45,485	37,485
Institutional Banking [Member] \| Trading and Investment Banking [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	155	301
Institutional Banking [Member] \| Service Charges On Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	13,890	12,577
Institutional Banking [Member] \| Brokerage Fees [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	1,484	1,319
Institutional Banking [Member] \| Bankcard Fees [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	5,331	4,813
Institutional Banking [Member] \| Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	424	404
Personal Banking [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	23,884	26,754
Noninterest income	23,709	32,300
Personal Banking [Member] \| Trust and Securities Processing [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	14,043	17,349
Personal Banking [Member] \| Service Charges On Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	1,737	1,424
Personal Banking [Member] \| Insurance Fees and Commissions [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	259	420
Personal Banking [Member] \| Brokerage Fees [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	1,939	1,951
Personal Banking [Member] \| Bankcard Fees [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	5,220	4,941
Personal Banking [Member] \| Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue Scope of ASC 606	$ 686	$ 669

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Amount of revenue that is not accounted for under Topic 606.

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