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Exit Activity Costs and Asset Impairments (Summary Of Exit Activity Costs And Asset Impairments by Segment) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Restructuring Cost and Reserve [Line Items] |  |  |
Inventory write-downs &/or asset impairment charges | $ (1,630) | $ 7,530 | $ 8,504
Exit activity costs | 7,125 | 6,217 | 1,418
Gain on sale leaseback |  |  | (6,799)
Total exit activity costs & asset impairments | 5,495 | 13,747 | 3,123
Corporate |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Inventory write-downs &/or asset impairment charges | 0 | 0 | 0
Exit activity costs | 261 | 58 | 0
Gain on sale leaseback |  |  | 0
Total exit activity costs & asset impairments | 261 | 58 | 0
Residential Products | Operating Segments |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Inventory write-downs &/or asset impairment charges | 345 | 1,459 | 6,495
Exit activity costs | 1,058 | 1,074 | 1,256
Gain on sale leaseback |  |  | (6,799)
Total exit activity costs & asset impairments | 1,403 | 2,533 | 952
Industrial and Infrastructure Products | Operating Segments |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Inventory write-downs &/or asset impairment charges | (2,484) | 4,221 | 2,009
Exit activity costs | 2,820 | 4,546 | 162
Gain on sale leaseback |  |  | 0
Total exit activity costs & asset impairments | 336 | 8,767 | 2,171
Renewable Energy & Conservation | Operating Segments |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Inventory write-downs &/or asset impairment charges | 509 | 1,850 | 0
Exit activity costs | 2,986 | 539 | 0
Gain on sale leaseback |  |  | 0
Total exit activity costs & asset impairments | $ 3,495 | $ 2,389 | $ 0

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- Definition Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.P.3) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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