Goodwill and Intangible Assets - Details of Goodwill (Detail) $ in Millions	6 Months Ended
Jun. 26, 2020 USD ($)
Goodwill [Line Items]
Goodwill	$ 171.1
Adjustments	0.0
Goodwill	171.1
SPS [Member]
Goodwill [Line Items]
Goodwill	97.6
Adjustments	0.0
Goodwill	97.6
SSB [Member]
Goodwill [Line Items]
Goodwill	73.5
Adjustments	0.0
Goodwill	$ 73.5

Amount after 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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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+ References

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