Debt Instrument Subject To Mandatory Redemption, Maximum Amount

No definition available.

Name:	efoi_DebtInstrumentSubjectToMandatoryRedemptionMaximumAmount
Namespace Prefix:	efoi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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+ Details

Name:	us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of transactions with related party during the financial reporting period.

+ References

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+ Details

Name:	us-gaap_RelatedPartyTransactionAmountsOfTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of new stock issued during the period.

+ References

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+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=efoi_A2021StreetervilleNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_DirectorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=efoi_OctoberPartitionedNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	efoi_PromissoryNoteAxis=efoi_PartitionedNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TypeOfArrangementAxis=efoi_ExchangeAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=efoi_HuangNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Subsequent Events (Details) - USD ($) $ in Thousands					1 Months Ended
Subsequent Events (Details) - USD ($) $ in Thousands	Nov. 09, 2022	Nov. 04, 2022	Oct. 10, 2022	Apr. 27, 2021	Oct. 31, 2022	Sep. 30, 2022	Apr. 30, 2022	Apr. 30, 2021
Subsequent Event [Line Items]
Proceeds from issuance of debt							$ 1,800	$ 1,500
2021 Streeterville Note
Subsequent Event [Line Items]
Proceeds from issuance of debt				$ 1,500
Principal amount				1,700
Maximum redemption amount				$ 205
Director
Subsequent Event [Line Items]
Proceeds from issuance of debt						$ 450
Subsequent Event \| October Partitioned Note
Subsequent Event [Line Items]
Principal amount			$ 205
Subsequent Event \| 2021 Streeterville Note \| Partitioned Note \| Exchange Agreement
Subsequent Event [Line Items]
Issuance of common stock (in shares)			385,918
Subsequent Event \| Director
Subsequent Event [Line Items]
Amounts of transaction	$ 350
Subsequent Event \| Huang Note \| Director
Subsequent Event [Line Items]
Amounts of transaction		$ 250
Proceeds from issuance of debt					$ 50