XML 18 R48.htm IDEA: XBRL DOCUMENT v2.4.1.9
Investment Securities, Gain Loss And Other Disclosures (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Security
Dec. 31, 2013
Gain (Loss) on Investments [Line Items]    
Number of investment securities held 264fmcb_NumberOfInvestmentSecuritiesHeld  
Number of loss positions less than twelve months 7fmcb_NumberOfLossPositionsLessThanTwelveMonths  
Number of loss positions in twelve months or more 6fmcb_NumberOfLossPositionsInTwelveMonthsOrMore  
Securities pledged to secure public deposits, FHLB borrowings, and other government agency deposits as required by law $ 178,800,000us-gaap_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged $ 334,800,000us-gaap_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged
Standby Letters of Credit [Member]    
Gain (Loss) on Investments [Line Items]    
Standby letter of credit issued by FHLB 165,000,000fmcb_LettersOfCreditProvidedByFHLB
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_StandbyLettersOfCreditMember
 
Letter of Credit maturity date Dec. 02, 2016  
Maintenance fee on letter of credit per annum (in hundredths) 0.10%us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_StandbyLettersOfCreditMember
 
Government Agency & Government Sponsored Entities [Member]    
Gain (Loss) on Investments [Line Items]    
Unrealized losses 3,000fmcb_MarketableSecuritiesGrossUnrealizedLosses
/ us-gaap_GainLossOnInvestmentsByCategoryAxis
= fmcb_GovernmentAgencyGovernmentSponsoredEntitiesMember
0fmcb_MarketableSecuritiesGrossUnrealizedLosses
/ us-gaap_GainLossOnInvestmentsByCategoryAxis
= fmcb_GovernmentAgencyGovernmentSponsoredEntitiesMember
Mortgage Backed Securities [Member]    
Gain (Loss) on Investments [Line Items]    
Unrealized losses 657,000fmcb_MarketableSecuritiesGrossUnrealizedLosses
/ us-gaap_GainLossOnInvestmentsByCategoryAxis
= us-gaap_MortgageBackedSecuritiesMember
7,600,000fmcb_MarketableSecuritiesGrossUnrealizedLosses
/ us-gaap_GainLossOnInvestmentsByCategoryAxis
= us-gaap_MortgageBackedSecuritiesMember
Obligations of States and Political Subdivisions [Member]    
Gain (Loss) on Investments [Line Items]    
Unrealized losses 10,000fmcb_MarketableSecuritiesGrossUnrealizedLosses
/ us-gaap_GainLossOnInvestmentsByCategoryAxis
= us-gaap_USStatesAndPoliticalSubdivisionsMember
627,000fmcb_MarketableSecuritiesGrossUnrealizedLosses
/ us-gaap_GainLossOnInvestmentsByCategoryAxis
= us-gaap_USStatesAndPoliticalSubdivisionsMember
Corporate Securities [Member]    
Gain (Loss) on Investments [Line Items]    
Unrealized losses   $ 147,000fmcb_MarketableSecuritiesGrossUnrealizedLosses
/ us-gaap_GainLossOnInvestmentsByCategoryAxis
= us-gaap_CorporateDebtSecuritiesMember
Municipal Bonds [Member]    
Gain (Loss) on Investments [Line Items]    
Percentage of portfolio rated at either issue or issuer level (in hundredths) 97.00%fmcb_PercentageOfPortfolioRatedAtEitherIssueOrIssuerLevel
/ us-gaap_GainLossOnInvestmentsByCategoryAxis
= us-gaap_MunicipalBondsMember
 
Percentage of portfolio not rated (in hundredths) 3.00%fmcb_PercentageOfBankQualifiedMunicipalBondPortfolioNotRated
/ us-gaap_GainLossOnInvestmentsByCategoryAxis
= us-gaap_MunicipalBondsMember