Goodwill And Other Intangible Assets (Summary of Finite-Lived Intangible Assets) (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Total other intangible assets, net	$ 18,858us-gaap_OtherIntangibleAssetsNet	$ 18,811us-gaap_OtherIntangibleAssetsNet	$ 18,050us-gaap_OtherIntangibleAssetsNet
Core deposit intangibles \| Community banking
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	25,881	29,379	40,770
Accumulated amortization	(14,192)	(17,879)	(30,209)
Net carrying amount	11,689	11,500	10,561
Customer list intangibles \| Specialty finance
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,800	1,800	1,800
Accumulated amortization	(971)	(941)	(842)
Net carrying amount	829	859	958
Customer list and other intangibles \| Wealth management
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	7,940	7,940	7,690
Accumulated amortization	(1,600)	(1,488)	(1,159)
Net carrying amount	$ 6,340	$ 6,452	$ 6,531

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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- Definition

The net carrying amount as of the balance sheet date of other indefinite-lived and finite-lived intangible assets that are not separately presented on the statement of financial position.

+ References

No definition available.

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