Business acquisition, maximum shares being exchanged for cash.

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Business acquisition, maximum shares being exchanged for stock.

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Business acquisition, number of shares issuable per share.

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Business combination, contingent consideration, measurement period end date.

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Business combination, contingent consideration, measurement period start date.

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Business combination, contingent consideration, term to pay after final determination of amount.

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- Definition

Fair value inputs earnings before interest taxes depreciation and amortization rate.

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- Definition

Volume weighted average stock price.

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No definition available.

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- Definition

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 6

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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- Definition

For contingent consideration arrangements and indemnification assets recognized in connection with a business combination, this element represents an estimate of the low-end of the potential range (undiscounted) of the consideration which may be paid.

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Amount of liability recognized arising from contingent consideration in a business combination.

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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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Business Acquisitions (Details Textual) (USD $)	0 Months Ended		3 Months Ended
Business Acquisitions (Details Textual) (USD $)	Jan. 27, 2015	Jul. 01, 2013	Mar. 31, 2015	Sep. 30, 2014	Jan. 26, 2015	Dec. 31, 2014
Business Acquisitions [Line Items]
Volume weighted average stock price over last 20 trading days, per share					$ 7.97fmnb_VolumeWeightedAverageStockPrice
National Bancshares Corporation
Business Acquisitions [Line Items]
Cash shareholders are entitled to elect to receive per share	$ 32.15
Shares shareholders are entitled to elect to receive per shares	4.034
Maximum shares exchanged for stock	80.00%
Maximum shares exchanged for cash	20.00%
Business combination, transaction value					$ 74,000,000
National Associates Incorporated
Business Acquisitions [Line Items]
Business Acquisition, Effective Date of Acquisition			Jul. 01, 2013
Fair value of total consideration transferred		4,400,000
Time to due date once final contingent consideration amount is determined			5 days
EBITDA measurement start date			Aug. 01, 2014
EBITDA measurement end date			Jul. 31, 2015
Contingent consideration		920,000	156,000			156,000
Goodwill, Impairment Loss				764,000
Decrease in contingent consideration				764,000
National Associates Incorporated \| Growth Percentage of EBITDA, Payment Tier 1
Business Acquisitions [Line Items]
Contingent future payments			0
National Associates Incorporated \| Growth Percentage of EBITDA, Payment Tier 2
Business Acquisitions [Line Items]
Contingent future payments			1,500,000
National Associates Incorporated \| Maximum
Business Acquisitions [Line Items]
Contingent future payments			1,500,000
National Associates Incorporated \| Maximum \| Growth Percentage of EBITDA, Payment Tier 1
Business Acquisitions [Line Items]
Fair value inputs, earnings before interest, taxes, depreciation, and amortization			6.00%
National Associates Incorporated \| Maximum \| Growth Percentage of EBITDA, Payment Tier 3
Business Acquisitions [Line Items]
Contingent future payments			$ 1,500,000
Fair value inputs, earnings before interest, taxes, depreciation, and amortization			12.00%
National Associates Incorporated \| Minimum \| Growth Percentage of EBITDA, Payment Tier 2
Business Acquisitions [Line Items]
Fair value inputs, earnings before interest, taxes, depreciation, and amortization			12.00%
National Associates Incorporated \| Minimum \| Growth Percentage of EBITDA, Payment Tier 3
Business Acquisitions [Line Items]
Fair value inputs, earnings before interest, taxes, depreciation, and amortization			6.00%