SHAREHOLDERS' EQUITY (Schedule of Stock Option Activity) (Details) - Employee Stock Option - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning balance (in shares)	1,184,847
Granted (in shares)	368,375
Exercised (in shares)	319,860
Cancelled (in shares)	2,765
Forfeited (in shares)	121,161
Ending balance (in shares)	1,109,436	1,184,847
Exercisable (in shares)	425,433
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Beginning balance (in usd per share)	$ 19.82
Granted (in usd per share)	17.86
Exercised (in usd per share)	16.46
Cancelled (in usd per share)	25.70
Forfeited (in usd per share)	1.20
Ending balance (in usd per share)	22.16	$ 19.82
Exercisable (in usd per share)	$ 40.08
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Outstanding at December 31	4 years 4 months 6 days	4 years 5 months 19 days
Exercisable	3 years 3 months 7 days
Aggregate intrinsic value
Outstanding at January 1	$ 104,731
Outstanding at December 31	147,545	$ 104,731
Exercisable	$ 48,955

Share Based Compensation Arrangement By Share Based Payment Award Options Aggregate Intrinsic Value [Abstract]

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Share based compensation arrangement by share based payment award options cancelled in period.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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