CREDIT LINES (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Maximum borrowing capacity under the credit agreement	$ 70,000
Credit facility for loans	50,000
Previous loan value under original Credit Facility		$ 10,000
Decrease in bank gaurantees per terms of amended Credit Facility	$ 15,000
Line of credit outstanding amount		50,000
Line of credit utilized		$ 5,000
Expiration date		Jun. 30, 2021
Allowed factoring amount		$ 20,000
Three Specific Customers [Member]
Debt Instrument [Line Items]
Allowed factoring amount		$ 60,000
Minimum [Member] \| Libor [Member]
Debt Instrument [Line Items]
Libor spread		2.10%
Maximum [Member] \| Libor [Member]
Debt Instrument [Line Items]
Libor spread		2.60%

The amount of credit facility available for loans.

No definition available.

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

- Definition

Decrease in bank gaurantees per terms of amended Credit Facility.

+ References

No definition available.

+ Details

Name:	crnt_DecreaseInBankGuaranteesCreditLines
Namespace Prefix:	crnt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Libor spread.

+ References

No definition available.

+ Details

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

- Definition

Line of credit utilized.

+ References

No definition available.

+ Details

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

- 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

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

- Definition

Previous loan value under original Credit Facility.

+ References

No definition available.

+ Details

Name:	crnt_PreviousLoanValuesUnderCreditFacilitiesBeforeAmendment
Namespace Prefix:	crnt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
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=120391452&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=120398452&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=120400017&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
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

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

- Details

Name:	srt_MajorCustomersAxis=crnt_ThreeSpecificCustomersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: