CREDIT LINES (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Maximum borrowing capacity under the credit agreement	$ 85,000
Credit facility for loans	40,000	$ 10,000
Increase in borrowing capacity	19,800
Line of credit outstanding amount		$ 40,000
Expiration date		Jun. 30, 2020
Allowed factoring amount	20,000	$ 20,000
Customer One [Member]
Debt Instrument [Line Items]
Allowed factoring amount	$ 50,000	94,000
Customer Two [Member]
Debt Instrument [Line Items]
Allowed factoring amount		$ 10,000
Minimum [Member] \| Libor [Member]
Debt Instrument [Line Items]
Libor spread		2.70%
Maximum [Member] \| Libor [Member]
Debt Instrument [Line Items]
Libor spread		3.00%

The amount of credit facility available for loans.

No definition available.

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Namespace Prefix:	crnt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of increase or (decrease) in the borrowing capacity of the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

Libor spread.

+ References

No definition available.

+ Details

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

- Definition

The maximum allowed amount of receivables that are able to be sold to a third party for a discount in a transaction called factoring.

+ References

No definition available.

+ Details

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Namespace Prefix:	crnt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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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Data Type:	xbrli:stringItemType
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://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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: 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(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-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

+ Details

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

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
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

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

- Details

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Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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