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RATIONALIZATION AND ASSET IMPAIRMENTS (Textual) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Rationalization and Asset Impairments
Rationalization and asset impairment charges (Note 6)	$ 6,257	$ 1,495	$ 36,016	$ 6,337
Business Exit Costs			14,089
Restructuring Reserve	11,744		11,744		$ 8,202
Americas Welding 2020 Plans [Member]
Rationalization and Asset Impairments
Restructuring Reserve	218		218
International Welding 2020 Plans [Member]
Rationalization and Asset Impairments
Restructuring Reserve	6,592		6,592
International Welding
Rationalization and Asset Impairments
Rationalization and asset impairment charges (Note 6)	2,401	$ 1,495	8,297	$ 4,621
Business Exit Costs			8,504
Restructuring Reserve	11,526		11,526		$ 8,202
International Welding 2019 Plans [Member]
Rationalization and Asset Impairments
Restructuring Reserve	$ 4,934		$ 4,934