Restructuring and Impairment Charges (Components of Restructuring and Impairment Charges) (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Sep. 30, 2020	Oct. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Restructuring and Impairment Charges [Abstract]
Impairment and loss on right of use asset	$ 17,540		$ 17,540
Lease termination gain		$ 2,445	15,200	$ 2,445
Impairment and loss on disposal of machinery and equipment			9,527	1,381
Employee severance and retention			3,285	1,332
Goodwill impairment				21,521
Other charges related to facility closure			3,173	582
Total restructuring and impairment charges			$ 18,325	$ 22,371

Impairment And Gain Loss On Sale Of Property Plant Equipment

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Amount of gain (loss) on termination of lease before expiration of lease term.

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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 loss from impairment of right-of-use asset from operating lease.

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Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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Amount of restructuring charges, remediation cost, and asset impairment loss.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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