Statements of Cash Flows (Parenthetical)	12 Months Ended
Dec. 31, 2022 USD ($)
Statements of Cash Flows [Abstract]
Deferred offering costs charged against certain proceeds from issuance of common stock	$ 95

Amount of deferred offering costs includes of offering costs charged against certain proceeds from the issuance of common stock.

No definition available.

Name:	femy_DeferredOfferingCostsChargedAgainstCertainProceedsFromIssuanceOfCommonStock
Namespace Prefix:	femy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration