RELEVANT STOCK OPTION INFORMATION (Details 4) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received from stock option exercises	$ 214	$ 201	$ 1,367
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of stock options vested based on grant date fair value	72	37	14
Intrinsic value of stock options exercised	1,082	494	3,362
Cash received from stock option exercises	918	680	6,105
Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options	$ 442	$ 204	$ 1,362
Weighted average grant date fair value of options granted (per share)	$ 12.43	$ 11.03	$ 0.00

Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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-Subparagraph (a)
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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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