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Exit Activity Costs and Asset Impairments (Summary of Exit Activity Costs and Asset Impairments by Segment) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Restructuring Cost and Reserve [Line Items] |  |  |  |
Inventory write-downs &/or asset impairment charges | $ 65 | $ (1,820) | $ (662) | $ (2,737)
Exit activity (recoveries) costs, net | 98 | 2,026 | 354 | 5,945
Total exit activity costs & asset impairments | 163 | 206 | (308) | 3,208
Residential Products |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Inventory write-downs &/or asset impairment charges | 0 | (126) | (43) | (147)
Exit activity (recoveries) costs, net | (29) | 207 | (152) | 392
Total exit activity costs & asset impairments | (29) | 81 | (195) | 245
Industrial and Infrastructure Products |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Inventory write-downs &/or asset impairment charges | 0 | (1,694) | (703) | (2,590)
Exit activity (recoveries) costs, net | (28) | 315 | 190 | 2,971
Total exit activity costs & asset impairments | (28) | (1,379) | (513) | 381
Renewable Energy & Conservation |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Inventory write-downs &/or asset impairment charges | 65 | 0 | 84 | 0
Exit activity (recoveries) costs, net | (68) | 1,369 | 49 | 2,419
Total exit activity costs & asset impairments | (3) | 1,369 | 133 | 2,419
Corporate |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Inventory write-downs &/or asset impairment charges | 0 | 0 | 0 | 0
Exit activity (recoveries) costs, net | 223 | 135 | 267 | 163
Total exit activity costs & asset impairments | $ 223 | $ 135 | $ 267 | $ 163

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