Note 3 - Discontinued Operations (Details) - Sale of Discontinued Operations (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Nov. 26, 2013
Plus:
Gain on sale of discontinued operations	$ 3,915
Pool and Commercial Products [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale proceeds	5,200	5,200
Less:
Trade accounts receivable, net	554
Inventories, net	721
Prepaid and other current assets	109
Property and equipment, net	73
Transaction costs	395
Plus:
Accounts payable	269
Accrued liabilities	298
Gain on sale of discontinued operations	$ 3,915

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

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

- Definition

Amount of gain (loss), before tax expense or benefit and not previously recognized, resulting from the sale of a business component.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

+ Details

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

- Definition

For the disposal group, including a component of the entity (discontinued operation), the aggregate of amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business and an amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection and net of any write-downs taken for collection uncertainty on the part of the holder, respectively.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying value of obligations incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

+ References

+ Details

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

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying value of obligations incurred and payable pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include interest, rent, salaries, and utilities.

+ References

+ Details

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

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying amount of inventories (net of all valuation allowances and write-downs).

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationInventory
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying amount as of the balance sheet date of assets not otherwise specified.

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of prepaid and other assets attributable to disposal group.

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationPrepaidAndOtherAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying value (net of accumulated depreciation and any write-downs) of tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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

- Definition

The value of all consideration given or received by the Entity in the significant acquisition or disposal.

+ References

No definition available.

+ Details

Name:	us-gaap_SignificantAcquisitionsAndDisposalsAcquisitionCostsOrSaleProceeds
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant