The percentage of eligible receivables which determines the amount of line of credit available.

No definition available.

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

- Definition

The threshold for determining the available line of credit with regards to the lessor of the percentage of lower of cost or market value of inventory or a predetermined value.

+ References

No definition available.

+ Details

Name:	efoi_LineOfCreditFacilityAvailableThresholdPercent
Namespace Prefix:	efoi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The threshold for determining the available line of credit with regards to the lessor of the percentage of lower of cost or market value of inventory or a predetermined value.

+ References

No definition available.

+ Details

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

- Definition

Right to Terminate, Notice Required, Period of Time

+ References

No definition available.

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate during the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

Name:	us-gaap_LineOfCreditFacilityInterestRateDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- Details

Name:	us-gaap_CreditFacilityAxis=efoi_PercentageOfInventoryLowerOfCostOrMarketValueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=efoi_InventoryMaximumValueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=efoi_BorrowingOnAccountsReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=efoi_BorrowingOnInventoriesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=efoi_BorrowingOnOverdraftsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Debt - Narrative (Details) - USD ($)	Dec. 22, 2011	Sep. 30, 2015	Dec. 31, 2014
Line of Credit Facility [Line Items]
Revolving line of credit, maximum	$ 4,500,000
Line of credit facility available, percentage of receivables	85.00%
Facility fee	1.00%
Credit line borrowings		$ 2,000	$ 453,000
Line of credit facility, remaining borrowing capacity		$ 4,500,000
Percentage Of Inventory Lower Of Cost Or Market Value [Member]
Line of Credit Facility [Line Items]
Line of credit facility available, threshold percent	50.00%
Inventory Maximum Value [Member]
Line of Credit Facility [Line Items]
Line of credit facility available, threshold value	$ 250,000
Borrowing On Accounts Receivable [Member]
Line of Credit Facility [Line Items]
Interest rate for borrowings	8.50%
Borrowing On Inventories [Member]
Line of Credit Facility [Line Items]
Interest rate for borrowings	10.00%
Borrowing On Overdrafts [Member]
Line of Credit Facility [Line Items]
Interest rate for borrowings	13.00%
Right to terminate, notice required, period of time	60 days