Restructuring and Impairment Charges (Schedule Of Restructuring Reserve Activity) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Restructuring Cost and Reserve [Line Items]
Accrued	$ 1,006
Cash Charges	4,169	$ 1,450
Non-cash charges	26,923	22,901
Cash payments	(1,816)	(84)
Accrued	3,359	1,366
Impairment And Loss On Right Of Use Assets [Member]
Restructuring Cost and Reserve [Line Items]
Non-cash charges	17,540
Impairment Charges For Leasehold Improvements And Equipment [Member]
Restructuring Cost and Reserve [Line Items]
Non-cash charges		1,380
Impairment And Loss On Disposal Of Machinery And Equipment [Member]
Restructuring Cost and Reserve [Line Items]
Non-cash charges	9,469
Employee Severance And Retention [Member]
Restructuring Cost and Reserve [Line Items]
Accrued	647
Cash Charges	3,371	1,318
Cash payments	(659)
Accrued	3,359	1,318
Other Charges Related To Facility Closure [Member]
Restructuring Cost and Reserve [Line Items]
Accrued	359
Cash Charges	798	132
Non-cash charges	(86)
Cash payments	$ (1,157)	(84)
Accrued		48
Goodwill Impairment [Member]
Restructuring Cost and Reserve [Line Items]
Non-cash charges		$ 21,521

Restructuring Reserve, Non-Cash Charges

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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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.

+ References

No definition available.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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