BASIC AND DILUTED NET LOSS PER SHARE (Summary of Reconciliation of Basic Weighted Average Number of Shares) (Details) - shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Shares used in computing net loss per ordinary shares, basic and diluted	50,504,698	48,017,188	45,552,199
The following items have been excluded from the diluted weighted average number of shares outstanding because they are anti-dilutive:
Stock options	7,447,519	7,676,713	8,212,554
Restricted share units	2,125,440	2,090,512	2,081,646
Outstanding options and RSU's excluded from the calculation of the diluted net loss per share	9,572,959	9,767,225	10,294,200

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1505-109256

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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