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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Goodwill And Other Intangible Assets (Narrative) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Indefinite-lived Intangible Assets [Line Items]
Goodwill increase (decrease) due to foreign currency translation adjustments			$ (1,033)
Amortization of other intangible assets	$ 997	$ 1,141	2,001	$ 2,305
Community banking
Indefinite-lived Intangible Assets [Line Items]
Goodwill increase			9,100
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			$ (1,033)
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