The percentage of net sales that must be paid as commission fees.

No definition available.

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- Definition

Related Party Transaction, Term of Agreement

+ References

No definition available.

+ Details

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- Definition

Related Party Transaction, Term of Agreement, Extension

+ 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

The amount of cash paid for commissions during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

+ Details

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- Definition

Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 8

-Article 5

+ Details

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

- 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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Namespace Prefix:	us-gaap_
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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Balance Type:	na
Period Type:	duration

- Details

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- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=efoi_CommunalMember
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- Details

Name:	dei_LegalEntityAxis=efoi_YehMeiChengMember
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Related Party Transactions - Narrative (Details) - USD ($)			3 Months Ended		6 Months Ended		40 Months Ended
	Jan. 01, 2013	Feb. 27, 2012	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Prepaid and other current assets			$ 1,084,000		$ 1,084,000		$ 1,084,000	$ 1,002,000
5 Elements Efficienties (BVI) Ltd [Member]
Related Party Transaction [Line Items]
Commission fee					5.00%
Ownership interest					50.00%
Communal [Member]
Related Party Transaction [Line Items]
Commission fee		5.00%			5.00%
Agreement term		60 months
Payments for commissions							0
Extension of agreement, terms	12 months
Recorded expenses under agreement			56,000	$ 56,000	$ 113,000	$ 113,000
Prepaid and other current assets			$ 113,000		$ 113,000		$ 113,000
Communal [Member] \| 5 Elements Efficienties (BVI) Ltd [Member] \| Yeh-Mei Cheng [Member]
Related Party Transaction [Line Items]
Ownership interest					50.00%