XML 12 R17.htm IDEA: XBRL DOCUMENT v2.4.0.8

FAIR VALUE OF INSTRUMENTS - Impaired Loans and Other Real Estate (Detail) (Fair Value on Nonrecurring Basis [Member], USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Change in fair value of assets and liabilities	$ (80)	$ (352)
Impaired loans [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total	1,562	4,591
Change in fair value of assets and liabilities		(76)
Other real estate owned residential mortgages [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total	886	783
Change in fair value of assets and liabilities	(16)	(62)
Other real estate owned commercial [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total	1,475	1,526
Change in fair value of assets and liabilities	(64)	(214)
Level 1 [Member] | Impaired loans [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total
Level 1 [Member] | Other real estate owned residential mortgages [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total
Level 1 [Member] | Other real estate owned commercial [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total
Level 2 [Member] | Impaired loans [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total
Level 2 [Member] | Other real estate owned residential mortgages [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total
Level 2 [Member] | Other real estate owned commercial [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total
Level 3 [Member] | Impaired loans [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total	1,562	4,591
Level 3 [Member] | Other real estate owned residential mortgages [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total	886	783
Level 3 [Member] | Other real estate owned commercial [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis, total	$ 1,475	$ 1,526

X

- Definition

Change In Fair Value Of Assets And Liabilities

+ References

No definition available.

+ Details

Name:	fmao_ChangeInFairValueOfAssetsAndLiabilities
Namespace Prefix:	fmao_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	fmao_FairValueOfAssetsAndLiabilitiesMeasuredOnNonRecurringBasisLineItems
Namespace Prefix:	fmao_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a nonrecurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

+ Details

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