Restructuring and Impairment Charges (Schedule Of Restructuring Reserve Activity) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Restructuring Cost and Reserve [Line Items]
Accrued	$ 1,847	$ 1,006
Cash Charges	6,437	4,169
Non-cash charges	93	26,923
Cash payments	(7,985)	(1,816)
Accrued	219	3,359
Impairment And Loss On Disposal Of Machinery And Equipment [Member]
Restructuring Cost and Reserve [Line Items]
Accrued	0
Cash Charges	0
Non-cash charges	269
Cash payments	0
Accrued	0
Impairment And Loss On Right Of Use Asset [Member]
Restructuring Cost and Reserve [Line Items]
Accrued		0
Cash Charges		0
Non-cash charges		17,540
Cash payments		0
Accrued		0
Loss On Disposal Of Machinery And Equipment [Member]
Restructuring Cost and Reserve [Line Items]
Accrued		0
Cash Charges		0
Non-cash charges		9,469
Cash payments		0
Accrued		0
Employee Severance And Retention [Member]
Restructuring Cost and Reserve [Line Items]
Accrued	1,596	647
Cash Charges	0	3,371
Non-cash charges	(80)	0
Cash payments	(1,297)	(659)
Accrued	219	3,359
Other Charges Related To Facility Closure [Member]
Restructuring Cost and Reserve [Line Items]
Accrued	251	359
Cash Charges	6,437	798
Non-cash charges	(96)	(86)
Cash payments	(6,688)	(1,157)
Accrued	$ 0	$ 0

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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
-Topic 420
-SubTopic 10
-Section 50
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3367-108585

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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://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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