PROPERTY, PLANT AND EQUIPMENT Rollforward (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017		Dec. 31, 2016
Movement in Property, Plant and Equipment [Roll Forward]
Opening balance		$ 89,080	[1]	$ 87,943
Additions		27,442		27,203
Disposals		(32)		(88)
Depreciation		(26,991)		(23,106)
Foreign currency movements		14,149		(2,872)
Ending balance	[1]	$ 103,648		$ 89,080

[1] Reflects property, plant and equipment, net.