Nature of Business - Additional Information (Detail)	12 Months Ended
Dec. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Current operating foreseeable future plan period after date of issued financial statements	1 year

Period of current cash resources to fund business.

No definition available.

Name:	fmi_PeriodOfCurrentCashResourcesToFundBusiness
Namespace Prefix:	fmi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration