Impaired Financing Receivable, With No Related Allowance, Related Allowance

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Impaired Financing Receivable, With Related Allowance, Related Allowance

+ References

No definition available.

+ Details

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

- Details

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

- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5258-111524

+ Details

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

- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953550-111524

+ Details

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

- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

+ Details

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

- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

+ Details

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

- Definition

Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of interest income, recognized on accrual basis, on financing receivables that are recognized as impaired, for which there is no related allowance for credit losses.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

+ Details

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

- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

+ Details

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

- Definition

Amount of average investment of impaired financing receivables for which there is a related allowance for credit losses.

+ References

+ Details

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

- Definition

Amount of interest income, recognized on accrual basis, on financing receivables, for which there is a related allowance for credit losses and are recognized as impaired.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

+ Details

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

- Definition

Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

+ Details

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

LOANS (Loans Individually Evaluated for Impairment by Class of Loans) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Commercial [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no related allowance recorded
Recorded Investment, With no related allowance recorded
Related Allowance, With no related allowance recorded
Average Recorded Investment, With no related allowance recorded
Interest Income Recognized, With no related allowance recorded
Unpaid Principal Balance, With a specific allowance recorded
Recorded Investment, With a specific allowance recorded
Related Allowance, With a specific allowance recorded
Average Recorded Investment, With a specific allowance recorded
Interest Income Recognized, With a specific allowance recorded
Unpaid Principal Balance, total
Recorded Investment, total
Related Allowance, total
Average Recorded Investment, total
Interest Income Recognized, total
Commercial Real Estate - Construction [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no related allowance recorded	1,589		1,589		1,589
Recorded Investment, With no related allowance recorded	173		173		173
Related Allowance, With no related allowance recorded
Average Recorded Investment, With no related allowance recorded	173	173	173	173
Interest Income Recognized, With no related allowance recorded
Unpaid Principal Balance, With a specific allowance recorded
Recorded Investment, With a specific allowance recorded
Related Allowance, With a specific allowance recorded
Average Recorded Investment, With a specific allowance recorded
Interest Income Recognized, With a specific allowance recorded
Unpaid Principal Balance, total	1,589		1,589		1,589
Recorded Investment, total	173		173		173
Related Allowance, total
Average Recorded Investment, total	173	173	173	173
Interest Income Recognized, total
Commercial Real Estate - Other [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no related allowance recorded	3,249		3,249		4,869
Recorded Investment, With no related allowance recorded	3,149		3,149		4,535
Related Allowance, With no related allowance recorded
Average Recorded Investment, With no related allowance recorded	3,172	758	3,195	751
Interest Income Recognized, With no related allowance recorded	33	11	60	26
Unpaid Principal Balance, With a specific allowance recorded	3,596		3,596		2,138
Recorded Investment, With a specific allowance recorded	3,596		3,596		2,127
Related Allowance, With a specific allowance recorded	322		322		101
Average Recorded Investment, With a specific allowance recorded	3,602	2,065	3,607	2,072
Interest Income Recognized, With a specific allowance recorded	20	20	39	48
Unpaid Principal Balance, total	6,845		6,845		7,007
Recorded Investment, total	6,745		6,745		6,662
Related Allowance, total	322		322		101
Average Recorded Investment, total	6,774	2,823	6,802	2,823
Interest Income Recognized, total	53	31	99	74
Consumer - Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no related allowance recorded	9		9		33
Recorded Investment, With no related allowance recorded	8		8		28
Related Allowance, With no related allowance recorded
Average Recorded Investment, With no related allowance recorded	9	134	10	135
Interest Income Recognized, With no related allowance recorded
Unpaid Principal Balance, With a specific allowance recorded
Recorded Investment, With a specific allowance recorded
Related Allowance, With a specific allowance recorded
Average Recorded Investment, With a specific allowance recorded
Interest Income Recognized, With a specific allowance recorded
Unpaid Principal Balance, total	9		9		33
Recorded Investment, total	8		8		28
Related Allowance, total
Average Recorded Investment, total	9	134	10	135
Interest Income Recognized, total
Consumer - Other [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no related allowance recorded					1
Recorded Investment, With no related allowance recorded					1
Related Allowance, With no related allowance recorded
Average Recorded Investment, With no related allowance recorded		15		15
Interest Income Recognized, With no related allowance recorded
Unpaid Principal Balance, With a specific allowance recorded
Recorded Investment, With a specific allowance recorded
Related Allowance, With a specific allowance recorded
Average Recorded Investment, With a specific allowance recorded
Interest Income Recognized, With a specific allowance recorded
Unpaid Principal Balance, total					1
Recorded Investment, total					1
Related Allowance, total
Average Recorded Investment, total		15		15
Interest Income Recognized, total
Residential [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no related allowance recorded	2,118		2,118		1,365
Recorded Investment, With no related allowance recorded	1,676		1,676		1,194
Related Allowance, With no related allowance recorded
Average Recorded Investment, With no related allowance recorded	1,793	1,848	1,797	1,861
Interest Income Recognized, With no related allowance recorded	1		2
Unpaid Principal Balance, With a specific allowance recorded					616
Recorded Investment, With a specific allowance recorded					616
Related Allowance, With a specific allowance recorded					141
Average Recorded Investment, With a specific allowance recorded
Interest Income Recognized, With a specific allowance recorded
Unpaid Principal Balance, total	2,118		2,118		1,981
Recorded Investment, total	1,676		1,676		1,810
Related Allowance, total					141
Average Recorded Investment, total	1,793	1,848	1,797	1,861
Interest Income Recognized, total	$ 1		$ 2