XML 65 R54.htm IDEA: XBRL DOCUMENT
v3.23.1

Stockholders' Equity - Outstanding Warrants from the January 2020 Equity Offering (Details) - $ / shares | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Jan. 31, 2020
January 2020 Equity Offering |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Warrants issued (in shares) | 229,414 | 229,414 |
Exercise price of common stock (USD per share) | $ 3.67 |  |
Jan. 2020 Investor Warrants |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Warrants issued (in shares) | 187,734 | 187,734 |
Sale of common stock (USD per share) | $ 3.3700 |  | $ 3.37
Jan. 2020 Placement Agent Warrants |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Warrants issued (in shares) | 41,680 | 41,680 |
Exercise price of common stock (USD per share) | $ 4.9940 |  |

X
- Definition Class Of Warrant Or Right, Warrants Issued + References No definition available. + Details
Name: | efoi_ClassOfWarrantOrRightWarrantsIssued
Namespace Prefix: | efoi_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Exercise price per share or per unit of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644 + Details
Name: | us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction. + References No definition available. + Details
Name: | us-gaap_SaleOfStockPricePerShare
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=efoi_January2020EquityOfferingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=efoi_January2020InstitutionalInvestorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=efoi_January2020EquityOfferingPrivatePlacementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |