Related Party Transaction, Term of Agreement

No definition available.

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- Definition

Related Party Transactions, Ownership in Reporting Entity by Related Party

+ References

No definition available.

+ Details

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- Definition

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

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- Details

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- Details

Name:	dei_LegalEntityAxis=efoi_YehMeiChengMember
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- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=efoi_CommunalMember
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Related Party Transactions (Details) - USD ($) $ in Thousands			12 Months Ended
	Jul. 31, 2014	Feb. 27, 2012	Dec. 31, 2015	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2017
5 Elements Global Advisors
Related Party Transaction [Line Items]
Ownership in reporting entity by related party						2.50%
5 Elements Efficiencies (BVI) Ltd.
Related Party Transaction [Line Items]
Ownership in reporting entity by related party						2.40%
5 Elements Efficiencies (BVI) Ltd. \| Yeh-Mei Cheng
Related Party Transaction [Line Items]
Ownership interest	50.00%
Communal
Related Party Transaction [Line Items]
Ownership in reporting entity by related party	5.00%
Related party transaction, term of agreement		60 months
Amount paid				$ 425	$ 523
Recorded expense			$ 226	$ 226
Communal \| 5 Elements Efficiencies (BVI) Ltd.
Related Party Transaction [Line Items]
Ownership interest	50.00%