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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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- Definition

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.

+ References

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

-Publisher FASB

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Amount of increase (decrease) 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 Intangible Assets - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Mar. 06, 2015	Mar. 05, 2015
Goodwill And Intangible Assets [Line Items]
Goodwill	$ 26,841us-gaap_Goodwill		$ 21,720us-gaap_Goodwill
Amortization of intangible assets	142us-gaap_AmortizationOfIntangibleAssets	202us-gaap_AmortizationOfIntangibleAssets
TCNB Financial Corp [Member]
Goodwill And Intangible Assets [Line Items]
Goodwill				5,121	5,121
Goodwill increased during period	$ 5,121