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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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 loss from the write-down 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.

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GOODWILL AND OTHER INTANGIBLE ASSETS, NET - Additional Information (Detail) - USD ($)		3 Months Ended
	Aug. 31, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 37,144,000		$ 37,144,000
Goodwill write-off	$ 0
Aggregate amortization expense		$ 620,000	$ 843,000
Core deposit intangibles
Finite-Lived Intangible Assets [Line Items]
Weighted average amortization period		5 years 2 months 4 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