RETIREMENT AND POSTRETIREMENT BENEFIT PLANS (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Domestic Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost		$ 39	$ 35	$ 117	$ 105
Interest cost		3,346	4,652	11,447	13,958
Expected return on plan assets		(6,009)	(6,245)	(17,431)	(18,735)
Amortization of prior service cost		0	0	0	0
Amortization of net loss		459	413	865	1,240
Settlement charges (1)	[1]	3,188	0	6,522	0
Defined benefit plans		1,023	(1,145)	1,520	(3,432)
Multi-employer plans		0	0	0	0
Defined contribution plans		4,945	5,506	15,322	17,205
Total pension cost		5,968	4,361	16,842	13,773
Foreign Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost		718	697	2,216	2,126
Interest cost		673	903	2,052	2,761
Expected return on plan assets		(1,076)	(1,087)	(3,097)	(3,317)
Amortization of prior service cost		15	16	46	47
Amortization of net loss		468	720	1,563	1,877
Settlement charges (1)	[1]	0	0	0	0
Defined benefit plans		798	1,249	2,780	3,494
Multi-employer plans		274	227	800	717
Defined contribution plans		931	692	2,406	1,615
Total pension cost		2,003	$ 2,168	5,986	$ 5,826
Americas Welding
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Settlement charges (1)		$ 3,188		$ 6,522

[1] Pension settlement charges resulting from lump sum pension payments in the three and nine months ended September 30, 2020.