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		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Indefinite-lived Intangible Assets [Line Items]
Goodwill recorded on acquisition			$ 10,726
Amortization of other intangible assets	$ 2,928	$ 1,163	8,827	$ 3,164
Community banking
Indefinite-lived Intangible Assets [Line Items]
Goodwill recorded on acquisition	$ 10,800		$ 10,726
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 recorded on acquisition			$ 0
Goodwill increase for foreign currency translation adjustments			$ 665
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 recorded on acquisition			$ 0
Goodwill, decrease for measurement period adjustments on acquisition			$ (340)
Wealth management \| Customer list intangibles
Indefinite-lived Intangible Assets [Line Items]
Amortization period in years, other intangible assets			10 years