Debt Instrument, Base Rate, Variable

No definition available.

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- Definition

Debt Instrument, Interest Rate, Stated Percentage, Collateral Management Fee

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Number Of Credit Facilities

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Amount Available Based On Qualified Accounts

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Facility, Annual Facility Fee, Period

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility, Annual Fee, Percent

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Line of Credit Facility, Available Amount Based On Qualified Accounts

+ References

No definition available.

+ Details

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

- Definition

Line of Credit Facility, Available Inventory

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Line of Credit Facility, Available Inventory, Net Realizable Value

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Borrowing Capacity, Inventory Costs, Percent

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Line of Credit Facility, Borrowing Capacity, Inventory Value, Percent

+ References

No definition available.

+ Details

Name:	efoi_LineOfCreditFacilityBorrowingCapacityInventoryValuePercent
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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Borrowing Capacity, Value Of Accounts Receivable, Percent

+ References

No definition available.

+ Details

Name:	efoi_LineOfCreditFacilityBorrowingCapacityValueOfAccountsReceivablePercent
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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Facility, Collateral Management Fee, Percent

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line Of Credit Facility, Minimum Requirement

+ References

No definition available.

+ Details

Name:	efoi_LineOfCreditFacilityMinimumRequirement
Namespace Prefix:	efoi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line Of Credit Facility, Monthly Facility Fee

+ References

No definition available.

+ Details

Name:	efoi_LineOfCreditFacilityMonthlyFacilityFee
Namespace Prefix:	efoi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line Of Credit Facility, Monthly Facility Fee, Percent

+ References

No definition available.

+ Details

Name:	efoi_LineOfCreditFacilityMonthlyFacilityFeePercent
Namespace Prefix:	efoi_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line Of Credit Facility, Overdraft Fee, Percent

+ References

No definition available.

+ Details

Name:	efoi_LineOfCreditFacilityOverdraftFeePercent
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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the fee that accompanies borrowing money under the debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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- 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
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- 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120391452&loc=d3e13212-122682

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current portion 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585

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Balance Type:	credit
Period Type:	duration

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
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Balance Type:	debit
Period Type:	instant

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

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- Details

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- Details

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Debt - Credit Facilities (Details)	Aug. 11, 2020 USD ($) creditFacility	Dec. 31, 2021 USD ($)	Apr. 20, 2021 USD ($)	Dec. 31, 2020 USD ($)	Aug. 30, 2020 creditFacility
Debt Instrument [Line Items]
Number of new credit facilities \| creditFacility	2				2
Credit line borrowings, net of loan origination fees		$ 2,169,000		$ 2,298,000
Amount available based on qualifying accounts	$ 4,500,000
Revolving Credit Facility \| Inventory Facility
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 3,000,000		$ 3,500,000
Inventory costs	75.00%
Inventory, net orderly liquidation value	85.00%
Stated interest rate	5.75%	22.40%		23.60%
Monthly service fee	1.00%
Minimum monthly fee	$ 18,000
Credit line borrowings, net of loan origination fees		$ 1,200,000		$ 1,300,000
Unamortized net issuance costs		$ 84,000		$ 121,000
Revolving Credit Facility \| Inventory Facility \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Stated interest rate	4.00%
Variable interest rate, base		0.21%		0.24%
Revolving Credit Facility \| Receivables Facility
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 2,500,000
Stated interest rate	2.00%	8.00%		7.90%
Monthly service fee	1.00%
Minimum monthly fee	$ 25,000
Percent of accounts receivable used as borrowing capacity	90.00%
Stated interest rate on collateral management fee		5.90%		5.90%
Credit line borrowings, net of loan origination fees		$ 1,000,000		$ 1,000,000
Unamortized net issuance costs		$ 24,000		$ 40,000
Revolving Credit Facility \| Receivables Facility \| Wall Street Journal, highest prime rate
Debt Instrument [Line Items]
Variable interest rate, base		3.25%		3.25%
Revolving Credit Facility \| Austin Facility
Debt Instrument [Line Items]
Annual facility period	3 years
Overdraft fee	2.00%
Annual fee	1.00%
Collateral management fee	0.50%
Payment amount	$ 1,400,000
Fee amount	100,000
Write off of remaining related debt and acquisition cost	59,000
Revolving Credit Facility \| Austin Credit Facility
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 5,000,000
Amount available under facility based on qualified accounts receivable	85.00%
Percent of net realizable value of eligible inventory	20.00%
Eligible inventory	$ 500,000
Minimum borrowing requirement	$ 1,000,000