ACCOUNTS RECEIVABLE (SCHEDULE OF CHANGE IN ALLOWANCE) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
ACCOUNTS RECEIVABLE AND SIGNIFICANT CLIENTS [Abstract]
Balance, beginning of year	$ 5,402	$ 5,579	$ 5,452	$ 5,592
Provision for credit losses	445		607
Uncollectible receivables written-off	(107)	(82)	(285)	(97)
Effect of foreign currency	55	(2)	21
Balance, end of year	$ 5,795	$ 5,495	$ 5,795	$ 5,495

No definition available.

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- Definition

Impact of foreign currency related to the rollforward of allowance for doubtful accounts between periods.

+ References

No definition available.

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- Definition

Amount of allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446

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- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

+ References

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