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Goodwill and Other Intangible Assets (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 30, 2017 | Dec. 31, 2016 | Dec. 26, 2015
Goodwill [Roll Forward] |  |  |  |  |
Goodwill |  |  | $ 169,657,000 |  |
Accumulated impairment charges, beginning of year |  |  | (49,405,000) |  |
Goodwill, net, beginning balance | $ 123,993,000 |  | 120,252,000 |  |
Additions | 3,852,000 | [1] | 4,601,000 | [2] |
Currency translation | 2,448,000 |  | (860,000) |  |
Goodwill | 179,698,000 |  |  |  | $ 169,657,000
Accumulated impairment loss, end of year | (49,405,000) |  |  |  | (49,405,000)
Goodwill, net, ending balance | 130,293,000 |  | 123,993,000 |  | 120,252,000
Impairment charges | 0 |  | 0 |  | 0
Great Lakes Copper, Inc [Member] |  |  |  |  |
Goodwill [Roll Forward] |  |  |  |  |
Purchase price allocation adjustments | 4,100,000 |  |  |  |
Jungwoo-Mueller [Member] |  |  |  |  |
Goodwill [Roll Forward] |  |  |  |  |
Purchase price allocation adjustments | 200,000 |  |  |  |
Piping Systems [Member] |  |  |  |  |
Goodwill [Roll Forward] |  |  |  |  |
Goodwill |  |  | 156,387,000 |  |
Accumulated impairment charges, beginning of year |  |  | (40,552,000) |  |
Goodwill, net, beginning balance | 119,576,000 |  | 115,835,000 |  |
Additions | 3,852,000 | [1] | 4,601,000 | [2] |
Currency translation | 2,448,000 |  | (860,000) |  |
Goodwill | 166,428,000 |  |  |  | 156,387,000
Accumulated impairment loss, end of year | (40,552,000) |  |  |  | (40,552,000)
Goodwill, net, ending balance | 125,876,000 |  | 119,576,000 |  | 115,835,000
Industrial Metals [Member] |  |  |  |  |
Goodwill [Roll Forward] |  |  |  |  |
Goodwill |  |  | 8,854,000 |  |
Accumulated impairment charges, beginning of year |  |  | (8,853,000) |  |
Goodwill, net, beginning balance | 1,000 |  | 1,000 |  |
Additions | 0 | [1] | 0 | [2] |
Currency translation | 0 |  | 0 |  |
Goodwill | 8,854,000 |  |  |  | 8,854,000
Accumulated impairment loss, end of year | (8,853,000) |  |  |  | (8,853,000)
Goodwill, net, ending balance | 1,000 |  | 1,000 |  | 1,000
Climate [Member] |  |  |  |  |
Goodwill [Roll Forward] |  |  |  |  |
Goodwill |  |  | 4,416,000 |  |
Accumulated impairment charges, beginning of year |  |  | 0 |  |
Goodwill, net, beginning balance | 4,416,000 |  | 4,416,000 |  |
Additions | 0 | [1] | 0 | [2] |
Currency translation | 0 |  | 0 |  |
Goodwill | 4,416,000 |  |  |  | 4,416,000
Accumulated impairment loss, end of year | 0 |  |  |  | 0
Goodwill, net, ending balance | $ 4,416,000 |  | $ 4,416,000 |  | $ 4,416,000
[1] | Includes finalization of the purchase price allocation adjustment for Jungwoo-Mueller of $0.2 million.
[2] | Includes finalization of the purchase price allocation adjustment for Great Lakes of $4.1 million.

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