SHARE-BASED COMPENSATION EXPENSE (Schedule of Share-Based Compensation, Stock Options Activity) (Details) - Stock Option [Member] $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($) $ / shares shares
Number of Shares
Number of Shares, Stock Option Outstanding, Beginning of Period \| shares	577
Number of Shares, Stock Option, Granted \| shares	0
Number of Shares, Stock Option, Exercised \| shares	(93)
Number of Shares, Stock Option, Forfeited/expired \| shares	0
Number of Shares, Stock Option Outstanding, End of Period \| shares	484
Number of Shares, Stock Option Exercisable \| shares	253
Number of Shares, Stock Option Vested and expected to vest \| shares	481
Weighted-Average Exercise Price Per Share
Weighted-Average Exercise Price Per Share, Stock Option Outstanding \| $ / shares	$ 16.04
Weighted-Average Exercise Price Per Share, Stock Option, Granted \| $ / shares	0.00
Weighted-Average Exercise Price Per Share, Stock Option, Exercised \| $ / shares	19.47
Weighted-Average Exercise Price Per Share, Stock Option, Forfeited/expired \| $ / shares	0.00
Weighted-Average Exercise Price Per Share, Stock Option Outstanding \| $ / shares	15.38
Weighted-Average Exercise Price Per Share, Stock Option Exercisable \| $ / shares	12.69
Weighted-Average Exercise Price Per Share, Stock Option Vested and expected to vest \| $ / shares	$ 15.37
Weighted-Average Remaining Contractual Life (in Years)
Weighted-Average Remaining Contractual Life (years), Stock Option Outstanding	4 years 3 months 26 days
Weighted-Average Remaining Contractual Life (years), Stock Option Exercisable	3 years 8 months 16 days
Weighted-Average Remaining Contractual Life (years), Stock Option Vested and expected to vest	4 years 3 months 22 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Stock Option Outstanding \| $	$ 19,424
Aggregate Intrinsic Value, Stock Option Exercisable \| $	10,826
Aggregate Intrinsic Value, Stock Option Vested and expected to vest \| $	$ 19,288

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.

+ References

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)-(4)
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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

No definition available.

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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.

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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.

+ References

No definition available.

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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 of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Weighted average remaining contractual term for fully vested and expected to vest options that are 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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- Definition

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

+ References

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-Name Accounting Standards Codification
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