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v3.20.4

Segment Information - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 26, 2020 | Dec. 28, 2019 | Dec. 29, 2018
Revenue from External Customer [Line Items] |  |  |
Impairment charges | $ 3,771 | $ 0 | $ 0
Gain on sale of manufacturing equipment | (132) | 963 | 253
Non-cash pension plan termination expense | 11,642 | 0 | 0
Gain (loss) on sale of assets | 0 | 963 | 253
Piping Systems [Member] |  |  |
Revenue from External Customer [Line Items] |  |  |
Impairment charges | 3,800 |  |
Gain on sale of real property |  | 1,200 | 1,400
Gain on sale of manufacturing equipment |  |  | 700
Operating Segments [Member] | Piping Systems [Member] |  |  |
Revenue from External Customer [Line Items] |  |  |
Impairment charges | 3,771 |  |
Gain (loss) on sale of assets |  | 1,194 | 2,093
Operating Segments [Member] | Industrial Metals [Member] |  |  |
Revenue from External Customer [Line Items] |  |  |
Impairment charges | $ 0 |  |
Gain (loss) on sale of assets |  | (275) | 1,301
Insurance recovery |  | $ 500 | $ 3,700

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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228 + Details
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- Definition Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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