OPERATING SEGMENTS, Revenues from External Customers and Segment Operating Profit Before Unallocated Expenses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]
Revenues	$ 140,150	$ 110,078	$ 397,532	$ 308,261
Operating profit	20,230	16,736	53,301	47,350
Russia [Member]
Segment Reporting Information [Line Items]
Revenues	11,534	10,554	36,464	29,045
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	140,139	110,075	397,489	308,222
Operating profit	27,597	22,158	76,735	63,125
Operating Segments [Member] | North America [Member]
Segment Reporting Information [Line Items]
Revenues	73,480	52,767	205,613	142,333
Operating profit	18,133	10,450	48,527	30,616
Operating Segments [Member] | Europe [Member]
Segment Reporting Information [Line Items]
Revenues	51,531	42,505	146,108	123,160
Operating profit	8,049	8,798	24,538	24,461
Operating Segments [Member] | Russia [Member]
Segment Reporting Information [Line Items]
Revenues	12,050	11,688	37,901	30,943
Operating profit	391	1,680	2,710	3,498
Operating Segments [Member] | Other Reportable Segments [Member]
Segment Reporting Information [Line Items]
Revenues	3,078	3,115	7,867	11,786
Operating profit	$ 1,024	$ 1,230	$ 960	$ 4,550