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Acquisitions (Narrative) (Details) - USD ($) $ in Thousands | Apr. 30, 2020 | Nov. 29, 2019
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Lansing Building Products, LLC [Member] |  |
Business Acquisition [Line Items] |  |
Percentage acquired | 91.00% |
Total purchase consideration | $ 556,200 |
Cash consideration | 556,200 |
Goodwill recognized | 295,600 |
Intangible Assets | 211,000 |
Redeemable noncontrolling interest from business acquisition | 43,600 |
Lansing Building Products, LLC [Member] | Customer relationships [Member] |  |
Business Acquisition [Line Items] |  |
Finite-lived intangible assets | $ 189,000 |
Definite-lived intangible assets, weighted-average amortization period | 16 years |
Lansing Building Products, LLC [Member] | Trade names [Member] |  |
Business Acquisition [Line Items] |  |
Finite-lived intangible assets | $ 22,000 |
Definite-lived intangible assets, weighted-average amortization period | 14 years |
VSC Fire & Security, Inc [Member] |  |
Business Acquisition [Line Items] |  |
Percentage acquired |  | 100.00%
Total purchase consideration |  | $ 225,000
Cash consideration |  | 204,000
Goodwill recognized |  | 124,900
Intangible Assets |  | 64,500
Expected tax deductible goodwill |  | 124,900
VSC Fire & Security, Inc [Member] | Customer relationships [Member] |  |
Business Acquisition [Line Items] |  |
Finite-lived intangible assets |  | $ 48,000
Definite-lived intangible assets, weighted-average amortization period |  | 12 years
VSC Fire & Security, Inc [Member] | Trade names [Member] |  |
Business Acquisition [Line Items] |  |
Finite-lived intangible assets |  | $ 14,000
Definite-lived intangible assets, weighted-average amortization period |  | 12 years
VSC Fire & Security, Inc [Member] | Other intangible assets [Member] |  |
Business Acquisition [Line Items] |  |
Finite-lived intangible assets |  | $ 2,500
Definite-lived intangible assets, weighted-average amortization period |  | 8 years

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- Definition Amount as of the acquisition date which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, in excessof the fair value off net assets acquired in one or more business combinations transactions. + References No definition available. + Details
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- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477 + Details
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- Definition Amount of intangible assets, excluding goodwill, acquired at the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472 + Details
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- Definition The amount of identifiable intangible assets recognized as of the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=116868840&loc=d3e2207-128464 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472 + Details
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