SHARE-BASED COMPENSATION EXPENSE (Schedule of Share-Based Compensation, Stock Options Activity) (Details) - Stock Option [Member] $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($) $ / shares shares
Number of Shares
Number of Shares, Stock Option Outstanding, Beginning of Period \| shares	306
Number of Shares, Stock Option, Granted \| shares	0
Number of Shares, Stock Option, Exercised \| shares	(101)
Number of Shares, Stock Option, Forfeited/expired \| shares	(1)
Number of Shares, Stock Option Outstanding, End of Period \| shares	204
Number of Shares, Stock Option Exercisable \| shares	159
Number of Shares, Stock Option Vested and expected to vest \| shares	203
Weighted-Average Exercise Price Per Share
Weighted-Average Exercise Price Per Share, Stock Option Outstanding \| $ / shares	$ 16.28
Weighted-Average Exercise Price Per Share, Stock Option, Granted \| $ / shares	0
Weighted-Average Exercise Price Per Share, Stock Option, Exercised \| $ / shares	19.16
Weighted-Average Exercise Price Per Share, Stock Option, Forfeited/expired \| $ / shares	20.94
Weighted-Average Exercise Price Per Share, Stock Option Outstanding \| $ / shares	14.83
Weighted-Average Exercise Price Per Share, Stock Option Exercisable \| $ / shares	13.12
Weighted-Average Exercise Price Per Share, Stock Option Vested and expected to vest \| $ / shares	$ 14.81
Weighted-Average Remaining Contractual Life (in Years)
Weighted-Average Remaining Contractual Life (years), Stock Option Outstanding	2 years 9 months
Weighted-Average Remaining Contractual Life (years), Stock Option Exercisable	2 years 3 months 25 days
Weighted-Average Remaining Contractual Life (years), Stock Option Vested and expected to vest	2 years 8 months 26 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Stock Option Outstanding \| $	$ 4,536
Aggregate Intrinsic Value, Stock Option Exercisable \| $	3,815
Aggregate Intrinsic Value, Stock Option Vested and expected to vest \| $	$ 4,525

Share based compensation arrangement by share based payment award options aggregate intrinsic value.

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- Definition

Share based compensation arrangement by share based payment award options outstanding weighted average remaining contractual life.

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No definition available.

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- Definition

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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- Definition

For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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- Definition

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

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- Definition

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

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

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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- Definition

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

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

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

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- Definition

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

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- Definition

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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- Definition

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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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Number of share options (or share units) exercised during the current period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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