SIGNIFICANT ACQUISITIONS AND DIVESTITURES - Fair Value of Assets Acquired and Liabilities Assumed (Details) € in Thousands, $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 13, 2019 USD ($)	May 27, 2019 USD ($)	May 27, 2019 EUR (€)
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Goodwill	$ 523,949	$ 529,463	$ 523,998
Zumbro
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Cash and cash equivalents				$ 686
Accounts receivable				3,314
Inventories				4,052
Prepaid & other current assets				521
Property, plant and equipment				15,245
Right of use assets				3,181
Other non-current assets				10
Accounts payable & accrued expenses				(1,651)
Lease liabilities				(3,181)
Debt				(5,345)
Deferred income taxes				(3,740)
Goodwill				18,505
Amount paid to shareholders				46,497
Debt paid on purchase date				5,345
Total amount paid on acquisition date				51,842
Zumbro | Customer relationships
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets				8,200
Zumbro | Developed technology
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets				4,400
Zumbro | Trade name
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets				$ 2,300
Chemogas
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Cash and cash equivalents					$ 4,412	€ 3,943
Accounts receivable					4,176
Inventories					957
Property, plant and equipment					15,972
Other non-current assets					1,491
Accounts payable & accrued expenses					(3,261)
Debt					(12,222)
Other liabilities					(1,030)
Pension obligation (net)					(594)
Deferred income taxes					(12,856)
Goodwill					59,319
Amount paid to shareholders					99,102
Debt paid on purchase date					12,222	€ 10,924
Total amount paid on acquisition date					111,324
Chemogas | Customer relationships
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets					39,158
Chemogas | Developed technology
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets					2,461
Chemogas | Trade name
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets					$ 1,119