Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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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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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Impairments of Goodwill and Other Long-Lived Assets - Summary (Details) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Impairment of goodwill		$ 48,671			$ 48,671
Impairment of other long-lived assets		12,438
Total impairments	$ 0	61,109		$ 0	61,109	$ 0
Performance Materials
Segment Reporting Information [Line Items]
Impairment of goodwill		48,671	$ 63,000		48,671
Impairment of other long-lived assets		12,438	$ 1,200
Total impairments		61,109
Technical Nonwovens
Segment Reporting Information [Line Items]
Impairment of goodwill		0			$ 0
Impairment of other long-lived assets		0
Total impairments		0
Thermal Acoustical Solutions
Segment Reporting Information [Line Items]
Impairment of goodwill		0
Impairment of other long-lived assets		0
Total impairments		$ 0