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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-Name Accounting Standards Codification
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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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GOODWILL AND OTHER INTANGIBLE ASSETS, NET - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Aggregate amortization expense	$ 1,322	$ 1,544
Goodwill	39,244		$ 39,244
Commercial Banking
Finite-Lived Intangible Assets [Line Items]
Goodwill	37,100
Mortgage Banking
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 2,100
Core deposit intangibles
Finite-Lived Intangible Assets [Line Items]
Weighted average amortization period	7 years 2 months 9 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	2 years 10 months