XML 43 R29.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Business Combination & Asset Purchase (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2017
Business Combinations [Abstract] |
Amortization Expense of Core Deposit Intangible Assets | Amortization expense of the core deposit intangible assets remaining is as follows:
|  | Custar |
2018 |  | $ | 167 |
2019 |  |  | 167 |
2020 |  |  | 161 |
Total |  | $ | 495 |

X
- Definition Tabular disclosure of information pertaining to the amortization expense of the core deposit intangible assets remaining. + References No definition available. + Details
Name: | fmao_AmortizationExpenseOfCoreDepositIntangibleAssetTableTextBlock
Namespace Prefix: | fmao_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_BusinessCombinationsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration