XML 32 R35.htm IDEA: XBRL DOCUMENT
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Loans - Loans Individually Evaluated for Impairment by Portfolio Class of Loans (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended
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Mar. 31, 2015 | Mar. 31, 2014
Consumer Real Estate [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment | $ 253 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember | $ 181 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember
Unpaid Principal Balance | 253 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember | 181 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember
Related Allowance | 35 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember | 44 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember
Average Recorded Investment | 269 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember | 668 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember
Interest Income Recognized | 3 fmao_ImpairedFinancingReceivablesInterestIncomeRecognized / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember | 1 fmao_ImpairedFinancingReceivablesInterestIncomeRecognized / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember
Agricultural Real Estate [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment |  | 141 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_AgricultureRealEstateMember
Unpaid Principal Balance |  | 141 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_AgricultureRealEstateMember
Average Recorded Investment |  | 505 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_AgricultureRealEstateMember
Agricultural [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment | 24 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_AgriculturalLoanMember |
Unpaid Principal Balance | 24 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_AgriculturalLoanMember |
Related Allowance | 24 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_AgriculturalLoanMember |
Average Recorded Investment | 24 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_AgriculturalLoanMember |
Commercial Real Estate [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment | 1,139 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember | 1,385 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember
Unpaid Principal Balance | 1,139 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember | 1,385 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember
Related Allowance | 131 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember | 107 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember
Average Recorded Investment | 852 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember | 2,396 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember
Interest Income Recognized |  | 14 fmao_ImpairedFinancingReceivablesInterestIncomeRecognized / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember
Commercial and Industrial [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment | 827 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember | 352 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember
Unpaid Principal Balance | 827 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember | 352 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember
Related Allowance | 238 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember | 110 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember
Average Recorded Investment | 806 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember | 1,993 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember
Interest Income Recognized | 7 fmao_ImpairedFinancingReceivablesInterestIncomeRecognized / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember | 16 fmao_ImpairedFinancingReceivablesInterestIncomeRecognized / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember
Consumer [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Average Recorded Investment | 7 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = us-gaap_ConsumerLoanMember |
With No Related Allowance Recorded [Member] | Consumer Real Estate [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment | 157 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember | 72 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
Unpaid Principal Balance | 157 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember | 72 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
Average Recorded Investment | 173 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember | 145 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
With No Related Allowance Recorded [Member] | Agricultural Real Estate [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment |  | 141 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_AgricultureRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
Unpaid Principal Balance |  | 141 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_AgricultureRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
Average Recorded Investment |  | 328 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_AgricultureRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
With No Related Allowance Recorded [Member] | Commercial Real Estate [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment |  | 904 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
Unpaid Principal Balance |  | 904 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
Average Recorded Investment |  | 2,112 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
Interest Income Recognized |  | 14 fmao_ImpairedFinancingReceivablesInterestIncomeRecognized / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
With No Related Allowance Recorded [Member] | Commercial and Industrial [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment | 467 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember |
Unpaid Principal Balance | 467 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember |
Average Recorded Investment | 469 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember | 25 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
Interest Income Recognized | 7 fmao_ImpairedFinancingReceivablesInterestIncomeRecognized / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember | 9 fmao_ImpairedFinancingReceivablesInterestIncomeRecognized / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithNoRelatedAllowanceRecordedMember
With a Specific Allowance Recorded [Member] | Consumer Real Estate [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment | 96 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 109 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
Unpaid Principal Balance | 96 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 109 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
Related Allowance | 35 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 44 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
Average Recorded Investment | 96 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 523 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
Interest Income Recognized | 3 fmao_ImpairedFinancingReceivablesInterestIncomeRecognized / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 1 fmao_ImpairedFinancingReceivablesInterestIncomeRecognized / us-gaap_FinancialInstrumentAxis = fmao_ConsumerRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
With a Specific Allowance Recorded [Member] | Agricultural Real Estate [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Average Recorded Investment |  | 177 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_AgricultureRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
With a Specific Allowance Recorded [Member] | Agricultural [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment | 24 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_AgriculturalLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember |
Unpaid Principal Balance | 24 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_AgriculturalLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember |
Related Allowance | 24 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_AgriculturalLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember |
Average Recorded Investment | 24 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_AgriculturalLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember |
With a Specific Allowance Recorded [Member] | Commercial Real Estate [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment | 1,139 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 481 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
Unpaid Principal Balance | 1,139 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 481 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
Related Allowance | 131 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 107 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
Average Recorded Investment | 852 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 284 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = us-gaap_CommercialRealEstateMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
With a Specific Allowance Recorded [Member] | Commercial and Industrial [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Investment | 360 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 352 fmao_ImpairedFinancingReceivableRecordedInvestmentDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
Unpaid Principal Balance | 360 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 352 fmao_ImpairedFinancingReceivableUnpaidPrincipalBalanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
Related Allowance | 238 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 110 fmao_ImpairedFinancingReceivableRelatedAllowanceDuringPeriod / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
Average Recorded Investment | 337 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember | 1,968 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
Interest Income Recognized |  | 7 fmao_ImpairedFinancingReceivablesInterestIncomeRecognized / us-gaap_FinancialInstrumentAxis = fmao_CommercialAndIndustrialMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember
With a Specific Allowance Recorded [Member] | Consumer [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Average Recorded Investment | $ 7 fmao_FinancingReceivableAverageRecordedInvestment / us-gaap_FinancialInstrumentAxis = us-gaap_ConsumerLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = fmao_WithSpecificAllowanceRecordedMember |

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