REVENUES FROM EXTERNAL CUSTOMERS AND SEGMENT OPERATING PROFIT BEFORE UNALLOCATED EXPENSES (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Segment Reporting Information [Line Items]
Revenues	$ 133,184	$ 103,800	$ 257,382	$ 198,183
Operating profit	17,535	16,830	33,071	30,614
Russia [Member]
Segment Reporting Information [Line Items]
Revenues	13,192	9,393	24,930	18,491
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	133,174	103,776	257,350	198,147
Operating profit	25,870	22,061	49,138	40,967
Operating Segments [Member] | North America [Member]
Segment Reporting Information [Line Items]
Revenues	69,076	46,703	132,133	89,566
Operating profit	16,213	10,440	30,394	20,166
Operating Segments [Member] | Europe [Member]
Segment Reporting Information [Line Items]
Revenues	48,424	40,794	94,577	80,655
Operating profit	8,118	7,003	16,489	15,663
Operating Segments [Member] | Russia [Member]
Segment Reporting Information [Line Items]
Revenues	13,498	9,778	25,851	19,255
Operating profit	1,687	1,499	2,319	1,818
Operating Segments [Member] | Other Reportable Segments [Member]
Segment Reporting Information [Line Items]
Revenues	2,176	6,501	4,789	8,671
Operating profit	$ (148)	$ 3,119	$ (64)	$ 3,320