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Goodwill and Intangible Assets - Narrative (Details) - USD ($) |  | 3 Months Ended |
--- | --- | --- | ---
Jul. 03, 2017 | Dec. 31, 2017 | Oct. 01, 2017
Goodwill [Line Items] |  |  |
Goodwill additions |  | $ 24,522,000 |
Impairment of goodwill | $ 0 |  |
GSG |  |  |
Goodwill [Line Items] |  |  |
Goodwill additions |  | 24,522,000 |
Gross amounts of goodwill |  | 403,400,000 | $ 379,500,000
Accumulated impairment |  | 17,700,000 | 17,700,000
CIG |  |  |
Goodwill [Line Items] |  |  |
Goodwill additions |  | 0 |
Gross amounts of goodwill |  | 475,600,000 | 477,000,000
Accumulated impairment |  | 97,900,000 | $ 97,900,000
Glumac |  |  |
Goodwill [Line Items] |  |  |
Goodwill additions |  | $ 24,500,000 |
Income approach |  |  |
Goodwill [Line Items] |  |  |
Weighted rate used in fair value of goodwill (as a percent) |  | 70.00% |
Discounted cash flow and market approach |  |  |
Goodwill [Line Items] |  |  |
Weighted rate used in fair value of goodwill (as a percent) |  | 30.00% |

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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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- Definition Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a,h) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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- Definition Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a,h) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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