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

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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 INTANGIBLES - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Jun. 30, 2012
Finite Lived Intangible Assets [Line Items]
Goodwill	$ 28,100,000us-gaap_Goodwill		$ 28,100,000us-gaap_Goodwill
Purchase credit card relationship intangible amount				24,500,000
Amortization expense	1,093,000us-gaap_AmortizationOfIntangibleAssets	1,235,000us-gaap_AmortizationOfIntangibleAssets
Purchased Credit Card Relationship Intangible [Member]
Finite Lived Intangible Assets [Line Items]
Purchase credit card relationship intangible amount	24,465,000		24,465,000
Amortization period of purchased credit card relationship intangible	6 years 8 months 12 days		7 years 9 months 18 days
Amortization expense	800,000	800,000
Core Deposits [Member]
Finite Lived Intangible Assets [Line Items]
Purchase credit card relationship intangible amount	45,844,000		45,844,000
Amortization period of purchased credit card relationship intangible	9 years 10 months 24 days		9 years 2 months 12 days
Amortization expense	$ 300,000	$ 400,000