RELATED PARTY BALANCES AND TRANSACTIONS (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Amount of surveys services		$ 900	$ 490
Revenues	$ 5,843	$ 6,745	3,336
Compass Networks [Member]
Related Party Transaction [Line Items]
Cash consideration			$ 833
Percentage of acquisitions		11.00%	14.00%
Rad Bynet [Member]
Related Party Transaction [Line Items]
Reimbursements for services provided	1,801	$ 2,242	$ 1,856
Fitel [Member]
Related Party Transaction [Line Items]
Revenues	5,594
Inventories [Member] \| Rad Bynet [Member]
Related Party Transaction [Line Items]
Expenses	83	152	78
Purchase Of Property And Equpment [Member]
Related Party Transaction [Line Items]
Expenses	274	46	148
Purchase Of Property And Equpment [Member] \| Rad Bynet [Member]
Related Party Transaction [Line Items]
Expenses	274	46	148
Rent And Maintenance [Member]
Related Party Transaction [Line Items]
Expenses	$ 2,099	$ 1,936	$ 1,960

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Fair value at acquisition-date of the assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interests issued by the acquirer, including but not limited to, instruments or interests issued or issuable in consideration for the business combination.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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