Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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GOODWILL AND OTHER INTANGIBLE ASSETS - Changes in Carrying Amount of Goodwill by Reporting Unit (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended	12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Sep. 30, 2019	Dec. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Beginning Balance		$ 133,912				$ 133,912	$ 196,963
Goodwill reduction							(662)
Goodwill impairment	$ (48,671)	(48,700)	$ (63,000)			(48,671)	(63,000)
Currency translation adjustment						2,354	611
Ending Balance			133,912			87,595	133,912
Performance Materials
Goodwill [Roll Forward]
Beginning Balance		80,658				80,658	144,626
Goodwill reduction				$ 600			(662)
Goodwill impairment	(48,671)		(63,000)			(48,671)	(63,000)
Currency translation adjustment						1	(306)
Ending Balance			80,658			31,988	80,658
Performance Materials \| Interface Performance Materials
Goodwill [Roll Forward]
Goodwill reduction					$ (1,300)
Technical Nonwovens
Goodwill [Roll Forward]
Beginning Balance		53,254				53,254	52,337
Goodwill reduction							0
Goodwill impairment	$ 0	$ 0				0	0
Currency translation adjustment						2,353	917
Ending Balance			$ 53,254			$ 55,607	$ 53,254