Goodwill and Other Acquisition-Related Intangible Assets (Narrative) (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Indefinite-lived Intangible Assets [Line Items]
Amortization of other acquisition-related intangible assets	$ 1,609	$ 2,007
Specialty finance
Indefinite-lived Intangible Assets [Line Items]
Goodwill increase (decrease) for foreign currency translation adjustments	$ 253
Core deposit intangibles \| Community banking
Indefinite-lived Intangible Assets [Line Items]
Amortization period in years, other intangible assets	10 years
Customer list intangibles \| Specialty finance
Indefinite-lived Intangible Assets [Line Items]
Amortization period in years, other intangible assets	18 years
Customer list intangibles \| Wealth management
Indefinite-lived Intangible Assets [Line Items]
Amortization period in years, other intangible assets	10 years

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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