Goodwill And Other Intangible Assets (Narrative) (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Indefinite-lived Intangible Assets [Line Items]
Goodwill increase (decrease) due to foreign currency translation adjustments	$ (616)
Amortization of other intangible assets	1,004	$ 1,164
Community banking
Indefinite-lived Intangible Assets [Line Items]
Goodwill increase	10,200
Goodwill increase (decrease) due to foreign currency translation adjustments	$ 0
Community banking \| Core deposit intangibles
Indefinite-lived Intangible Assets [Line Items]
Amortization period in years, other intangible assets	10 years
Specialty finance
Indefinite-lived Intangible Assets [Line Items]
Goodwill increase (decrease) due to foreign currency translation adjustments	$ (616)
Specialty finance \| Customer list intangibles
Indefinite-lived Intangible Assets [Line Items]
Amortization period in years, other intangible assets	18 years
Wealth management
Indefinite-lived Intangible Assets [Line Items]
Goodwill increase (decrease) due to foreign currency translation adjustments	$ 0
Wealth management \| Customer list intangibles
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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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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.

+ References

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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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