COMMITMENTS AND CONTINGENCIES (Details) (USD $)	12 Months Ended				12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Mar. 01, 2014 Subsequent Event	Dec. 31, 2013 Foreign exchange forward contracts	Dec. 31, 2012 Foreign exchange forward contracts	Dec. 31, 2013 Foreign exchange forward contracts Subsequent Event	Dec. 31, 2013 Nondesignated hedges	Dec. 31, 2012 Nondesignated hedges	Dec. 31, 2013 Designated hedges Foreign exchange forward contracts	Dec. 31, 2012 Designated hedges Foreign exchange forward contracts
Exchange rate
Percentage of appreciation or depreciation of Russian ruble against US dollar	(7.00%)	6.00%	(5.00%)
Change in average percentage of the average value of the Russian Ruble against the US Dollar against corresponding prior period	2.00%
Average exchange rate (in ruble)	31.85
Exchange rate (in ruble)	32.73			36.18
Derivative financial instruments
Notional amount							$ 59,400,000	$ 155,600,000	$ 81,500,000	$ 82,500,000	$ 87,900,000
Effect of derivative financial instruments designated as fair value hedges on consolidated statement of income
Foreign currency gains (losses) designated as hedging instruments					916,000	(1,233,000)
Effect of outstanding economic hedges
Foreign currency gains (losses) not designated as hedging instruments					$ 2,033,000	$ (272,000)