RESTRUCTURING CHARGES (Restructuring Reserve) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Restructuring Reserve [Roll Forward]
Balance at December 31, 2015			$ 1,409
Restructuring	$ 226	$ 0	426	$ 0
Cash expenditures			(1,183)
Foreign currency translation adjustment			41
Balance at June 30, 2016	693		693
Employee termination costs
Restructuring Reserve [Roll Forward]
Restructuring	69		269
Other related costs
Restructuring Reserve [Roll Forward]
Restructuring	157		157
Operating segment | MMS
Restructuring Reserve [Roll Forward]
Balance at December 31, 2015			167
Restructuring	0		0
Cash expenditures			(10)
Foreign currency translation adjustment			0
Balance at June 30, 2016	157		157
Operating segment | MMS | Employee termination costs
Restructuring Reserve [Roll Forward]
Restructuring	0		0
Operating segment | MMS | Other related costs
Restructuring Reserve [Roll Forward]
Restructuring	0		0
Operating segment | ATA
Restructuring Reserve [Roll Forward]
Balance at December 31, 2015			1,242
Restructuring	226		426
Cash expenditures			(1,173)
Foreign currency translation adjustment			41
Balance at June 30, 2016	536		536
Operating segment | ATA | Employee termination costs
Restructuring Reserve [Roll Forward]
Restructuring	69		269
Operating segment | ATA | Other related costs
Restructuring Reserve [Roll Forward]
Restructuring	$ 157		$ 157