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

No definition available.

Name:	efoi_CommissionFeePercent
Namespace Prefix:	efoi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	efoi_Note11RelatedPartyTransactionsDetailsLineItems
Namespace Prefix:	efoi_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents term of agreement with related party.

+ References

No definition available.

+ Details

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Namespace Prefix:	efoi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPManagingMemberOrGeneralPartnerOwnershipInterest
Namespace Prefix:	us-gaap_
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=56944662&loc=d3e3536-108585

+ Details

Name:	us-gaap_PaymentsForCommissions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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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Namespace Prefix:	us-gaap_
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

- Details

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

- Details

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Note 11 - Related Party Transactions (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Note 11 - Related Party Transactions (Details) [Line Items]
Prepaid Expense and Other Assets, Current	991		$ 1,002
5 Elements Efficienties (BVI) Ltd [Member] \| Communal [Member] \| Yeh-Mei Cheng [Member]
Note 11 - Related Party Transactions (Details) [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	50.00%
5 Elements Efficienties (BVI) Ltd [Member]
Note 11 - Related Party Transactions (Details) [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	50.00%
Communal [Member] \| Prepaid Expenses and Other Current Assets [Member]
Note 11 - Related Party Transactions (Details) [Line Items]
Prepaid Expense and Other Assets, Current	170
Communal [Member]
Note 11 - Related Party Transactions (Details) [Line Items]
Related Party Transaction, Term of Agreement	60 months
Commission Fee, Percent	5.00%
Payments for Commissions	0
Related Party Transaction, Expenses from Transactions with Related Party	56	$ 56