INCOME TAXES (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Holiday [Line Items]
Undistributed Earnings of Foreign Subsidiaries	$ 443,200
Aggregate dollar benefits from tax holidays	$ 20,800	$ 16,800	$ 9,700
Income tax holiday benefit (in dollars per share)	$ 0.40	$ 0.34	$ 0.20
Unrecognized tax benefits	$ 62	$ 200	$ 1,271	$ 1,271
Penalties and interest	0	12	$ 189
Unrecognized tax benefits with favorable impact	$ 62	$ 212
Belarus
Income Tax Holiday [Line Items]
Exemption (as a percent)	100.00%
Federal income tax rate (as a percent)	18.00%
Tax exemption period (in years)	15 years
Income tax holiday description	On September 22, 2005, the president of Belarus signed the decree “On the High-Technologies Park” (the “Decree”). The Decree is aimed at boosting the country’s high-technology sector. The Decree stipulates that member technology companies have a 100% exemption from Belarusian income tax of 18% effective July 1, 2006. The Decree is in effect for a period of 15 years from July 1, 2006.

INCOME TAXES (Narrative) (Details) - USD ($)
$ / shares in Units, $ in Thousands

12 Months Ended

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Income Tax Holiday [Line Items]

Undistributed Earnings of Foreign Subsidiaries

$ 443,200

Aggregate dollar benefits from tax holidays

$ 20,800

$ 16,800

$ 9,700

Income tax holiday benefit (in dollars per share)

$ 0.40

$ 0.34

$ 0.20

Unrecognized tax benefits

$ 62

$ 200

$ 1,271

Penalties and interest

$ 189

Unrecognized tax benefits with favorable impact

$ 62

$ 212

Belarus

Income Tax Holiday [Line Items]

Exemption (as a percent)

100.00%

Federal income tax rate (as a percent)

18.00%

Tax exemption period (in years)

15 years

Income tax holiday description

On September 22, 2005, the president of Belarus signed the decree “On the High-Technologies Park” (the “Decree”). The Decree is aimed at boosting the country’s high-technology sector. The Decree stipulates that member technology companies have a 100% exemption from Belarusian income tax of 18% effective July 1, 2006. The Decree is in effect for a period of 15 years from July 1, 2006.

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The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations.

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The amount of income taxes from which a reporting entity is exempt or for which it will receive a reduction in income taxes as a result of the income tax holiday granted by the taxing jurisdiction.

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Per share amount effect of the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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