Amount of accumulated impairment loss for 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 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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Goodwill (Details)	3 Months Ended			12 Months Ended
Goodwill (Details)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($) segment
Goodwill [Line Items]
Goodwill impairment	$ 0	$ 0	$ 0
Number of reportable segments \| segment				2
Advanced Materials & Structures
Goodwill [Line Items]
Accumulated impairment losses	0			$ 0
Engineered Papers
Goodwill [Line Items]
Accumulated impairment losses	$ 2,700,000			$ 2,700,000