Number of installments.

No definition available.

Name:	eltk_NumberOfInstallments
Namespace Prefix:	eltk_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Payment for lease of car.

+ References

No definition available.

+ Details

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Namespace Prefix:	eltk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of bonus given to officers.

+ References

No definition available.

+ Details

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Namespace Prefix:	eltk_
Data Type:	num:percentItemType
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- Definition

Percentage of commission.

+ References

No definition available.

+ Details

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Namespace Prefix:	eltk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of discount on excess inventory.

+ References

No definition available.

+ Details

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Namespace Prefix:	eltk_
Data Type:	num:percentItemType
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- Definition

Percentage of mark up related to actual price of purchase.

+ References

No definition available.

+ Details

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Namespace Prefix:	eltk_
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- Definition

Percentage of standard discount.

+ References

No definition available.

+ Details

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Namespace Prefix:	eltk_
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Balance Type:	na
Period Type:	duration

- Definition

Reimbursement expense.

+ References

No definition available.

+ Details

Name:	eltk_ReimbursementExpense
Namespace Prefix:	eltk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage discount on purchases.

+ References

No definition available.

+ Details

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Namespace Prefix:	eltk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Expenditures for salaries of officers. Does not include allocated share-based compensation, pension and post-retirement benefit expense or other labor-related non-salary expense. For commercial and industrial companies, excludes any direct and overhead labor that is included in cost of goods sold.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Definition

The cash inflow from a long-term borrowing made from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from Advances from Affiliates.

+ References

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

- Definition

Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

No definition available.

+ Details

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

- Definition

Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=eltk_NistecMember
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Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
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Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

Name:	us-gaap_CurrencyAxis=currency_ILS
Namespace Prefix:
Data Type:	na
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RELATED PARTY BALANCES AND TRANSACTIONS (Narrative) (Details) ₪ in Thousands, $ in Thousands	1 Months Ended									12 Months Ended
	Apr. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2018 ILS (₪)	Nov. 30, 2017 USD ($)	Nov. 30, 2017 ILS (₪)	Jul. 30, 2017 USD ($)	Jul. 30, 2017 ILS (₪)	Jun. 30, 2017 USD ($)	Jun. 30, 2017 ILS (₪)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 ILS (₪)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Related Party Transaction [Line Items]
Proceeds from related party debt \| $										$ 1,442
Nistec [Member]
Related Party Transaction [Line Items]
Percentage discount on purchases										10.00%	10.00%
Percentage of mark up related to actual price of purchase										20.00%	20.00%
Percentage of discount on excess inventory										50.00%	50.00%
Percentage of standard discount										5.00%	5.00%
Percentage of commission										14.25%	14.25%
Percentage of bonus given to officers										2.00%	2.00%
Proceeds from related party debt \| $								$ 1,400
Interest rate								2.60%	2.60%
Number of installments								8	8
Loan term								2 years	2 years
Nistec [Member] \| Subsequent Event [Member]
Related Party Transaction [Line Items]
Proceeds from related party debt \| $	$ 2,500	$ 1,100
Nistec [Member] \| Bank HaPoalim [Member]
Related Party Transaction [Line Items]
Proceeds from line of credit \| $						$ 1,300
Period of line of credit						1 year	1 year
Nistec [Member] \| Mizrahi-Tefahot Bank [Member]
Related Party Transaction [Line Items]
Proceeds from related party debt \| $				$ 840
Nistec [Member] \| NIS [Member]
Related Party Transaction [Line Items]
Total purchases											₪ 300
Bonus											200
Reimbursement expense											10
Proceeds from related party debt									₪ 5,000
Nistec [Member] \| NIS [Member] \| Subsequent Event [Member]
Related Party Transaction [Line Items]
Proceeds from related party debt			₪ 4,000
Nistec [Member] \| NIS [Member] \| Bank HaPoalim [Member]
Related Party Transaction [Line Items]
Proceeds from line of credit							₪ 4,500
Nistec [Member] \| NIS [Member] \| Mizrahi-Tefahot Bank [Member]
Related Party Transaction [Line Items]
Proceeds from related party debt					₪ 3,000
Nistec [Member] \| NIS [Member] \| Chief Executive Officer [Member]
Related Party Transaction [Line Items]
Payment for lease of car											₪ 250