Financing receivable acquired loans.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Financing receivable allowance for credit loss acquired with deteriorated credit quality.

+ References

No definition available.

+ Details

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Namespace Prefix:	fmnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Loans (Details 4) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 95	$ 96
Collectively evaluated for impairment	11,218	10,603
Acquired loans	6	153
Total ending allowance balance	11,319	10,852	$ 9,390	$ 8,978
Loans:
Loans individually evaluated for impairment	6,295	7,338
Loans collectively evaluated for impairment	1,100,621	1,048,074
Acquired loans	352,755	370,359
Acquired with deteriorated credit quality	798,284	779,340
Loans	1,461,461	1,427,635
Receivables Acquired with Deteriorated Credit Quality
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	1,790	1,864
Commercial real estate
Ending allowance balance attributable to loans:
Individually evaluated for impairment	35	44
Collectively evaluated for impairment	3,603	3,491
Acquired loans	0	42
Total ending allowance balance	3,638	3,577	3,181	3,127
Loans:
Loans individually evaluated for impairment	2,306	3,457
Loans collectively evaluated for impairment	397,475	376,632
Acquired loans	147,563	153,228
Loans	548,272	534,285
Commercial real estate \| Receivables Acquired with Deteriorated Credit Quality
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	928	968
Commercial
Ending allowance balance attributable to loans:
Individually evaluated for impairment	4	4
Collectively evaluated for impairment	1,842	1,763
Acquired loans	0	107
Total ending allowance balance	1,846	1,874	1,452	1,373
Loans:
Loans individually evaluated for impairment	336	477
Loans collectively evaluated for impairment	204,206	195,146
Acquired loans	44,608	48,536
Loans	250,012	245,055
Commercial \| Receivables Acquired with Deteriorated Credit Quality
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	862	896
Residential real estate
Ending allowance balance attributable to loans:
Individually evaluated for impairment	56	48
Collectively evaluated for impairment	2,259	2,153
Acquired loans	6	4
Total ending allowance balance	2,321	2,205	1,914	1,845
Loans:
Loans individually evaluated for impairment	3,601	3,308
Loans collectively evaluated for impairment	296,612	280,215
Acquired loans	140,883	146,672
Loans	441,096	430,195
Residential real estate \| Receivables Acquired with Deteriorated Credit Quality
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	0	0
Consumer
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	2,813	2,766
Acquired loans	0	0
Total ending allowance balance	2,813	2,766	2,218	2,160
Loans:
Loans individually evaluated for impairment	52	96
Loans collectively evaluated for impairment	202,328	196,081
Acquired loans	19,701	21,923
Loans	222,081	218,100
Consumer \| Receivables Acquired with Deteriorated Credit Quality
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	0	0
Unallocated
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	701	430
Acquired loans	0	0
Total ending allowance balance	701	430	$ 625	$ 473
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	0	0
Acquired loans	0	0
Loans	0	0
Unallocated \| Receivables Acquired with Deteriorated Credit Quality
Ending allowance balance attributable to loans:
Acquired with deteriorated credit quality	0	0
Loans:
Acquired with deteriorated credit quality	$ 0	$ 0