SEGMENT AND GEOGRAPHIC REGION INFORMATION (Details 3) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Sales to clients attributed to the geographic areas based on the origin of sale
Sales	$ 305,734	$ 263,588	$ 268,622	$ 266,498	$ 286,453	$ 268,297	$ 265,943	$ 229,601	$ 1,104,442	$ 1,050,294	$ 862,252
Property, plant, and equipment, net	172,142				165,019				172,142	165,019	137,893
United States
Sales to clients attributed to the geographic areas based on the origin of sale
Sales									979,221	928,733	752,347
Property, plant, and equipment, net	137,863				123,821				137,863	123,821	94,896
Canada
Sales to clients attributed to the geographic areas based on the origin of sale
Sales									36,163	32,811	36,240
Property, plant, and equipment, net	20,919				25,669				20,919	25,669	27,938
Europe
Sales to clients attributed to the geographic areas based on the origin of sale
Sales									89,058	88,750	73,665
Property, plant, and equipment, net	$ 13,360				$ 15,529				$ 13,360	$ 15,529	$ 15,059