GOODWILL AND INTANGIBLE ASSETS (Details 2) (USD $) In Thousands, unless otherwise specified	1 Months Ended	12 Months Ended
	Jul. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Intangible Assets
Accumulated amortization and foreign currency translation		$ 52,557	$ 42,210
Net carrying value		48,382
Total gross		101,049	100,237
Unamortized intangible assets, Proprietary knowledge		110	110
Total net carrying value		48,492	58,027
Patents purchased	3,100
Weighted average amortization period of intangible assets		6 years
Amortization expense		11,293	12,190	7,815
Expected amortization expense for the definite lived intangible assets
2013		9,465
2014		8,714
2015		8,618
2016		6,592
2017		3,204
Thereafter		11,789
Customer relationships
Intangible Assets
Gross amount		77,426	77,151
Accumulated amortization and foreign currency translation		35,597	27,606
Net carrying value		41,829	49,545
Trade names
Intangible Assets
Gross amount		8,951	8,951
Accumulated amortization and foreign currency translation		6,181	5,719
Net carrying value		2,770	3,232
Core technology
Intangible Assets
Gross amount		6,400	6,400
Accumulated amortization and foreign currency translation		5,835	4,777
Net carrying value		565	1,623
Non-compete agreements
Intangible Assets
Gross amount		3,874	3,874
Accumulated amortization and foreign currency translation		3,656	3,463
Net carrying value		218	411
Favorable lease agreements
Intangible Assets
Gross amount		620	620
Accumulated amortization and foreign currency translation		500	420
Net carrying value		120	200
Patents
Intangible Assets
Gross amount		3,131	3,131
Accumulated amortization and foreign currency translation		723	225
Net carrying value		2,408	2,906
Licenses
Intangible Assets
Gross amount		537
Accumulated amortization and foreign currency translation		65
Net carrying value		$ 472