Corporate Restructuring Costs (Reconciliation Of Restructuring Liability) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, beginning balance	$ 30
Charges	6,399
Payments	(6,429)
Restructuring Reserve, ending balance	0
Employee Severance And Other Employee Transition Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, beginning balance	0
Charges	303
Payments	(303)
Restructuring Reserve, ending balance	0
Recruitment And Relocation Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, beginning balance	30
Charges	874
Payments	(904)
Restructuring Reserve, ending balance	0
Third-party And Other Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, beginning balance	0
Charges	5,222
Payments	(5,222)
Restructuring Reserve, ending balance	$ 0

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.

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- Definition

Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b)(1))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(d))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

+ Details

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- Definition

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.

+ Details

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- Definition

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://fasb.org/us-gaap/role/ref/legacyRef
-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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
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-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

+ Details

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- Details

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