Number Of Branches Sold.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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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Remaining amortization period 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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Amount after accumulated impairment loss 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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Amount of transfers of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized among segments.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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GOODWILL AND OTHER INTANGIBLE ASSETS, NET - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) Branch	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 39,244		$ 39,244		$ 31,591
Finite-Lived Intangible Assets [Line Items]
Impairment on intangible assets	0	$ 0	$ 258	$ 0
Number of branches sold \| Branch			2
Aggregate amortization expense	$ 1,401	$ 890	$ 4,490	$ 2,773
Commercial Banking
Finite-Lived Intangible Assets [Line Items]
Goodwill transferred between segments			37,100
Mortgage Banking
Finite-Lived Intangible Assets [Line Items]
Goodwill transferred between segments			2,100
Core deposit intangibles
Finite-Lived Intangible Assets [Line Items]
Impairment on intangible assets			$ 258
Weighted average amortization period			7 years 6 months 26 days
Core deposit intangibles \| Minimum
Finite-Lived Intangible Assets [Line Items]
Amortization period of other intangible assets			4 years
Core deposit intangibles \| Maximum
Finite-Lived Intangible Assets [Line Items]
Amortization period of other intangible assets			10 years
Customer relationship intangible
Finite-Lived Intangible Assets [Line Items]
Amortization period of other intangible assets			5 years
Remaining amortization period			3 years 3 months 29 days