Acquisitions - Pro Forma Financial Information (Details) - CPI ASC Signal Division, Inc. $ / shares in Units, $ in Millions	9 Months Ended
Sep. 27, 2020 USD ($) $ / shares
Business Acquisition [Line Items]
Pro forma revenues	$ 559.1
Pro forma net loss before tax	(0.7)
Pro forma net loss	$ (3.4)
Basic pro forma loss per share (USD per share) \| $ / shares	$ (0.03)
Diluted pro forma loss per share (USD per share) \| $ / shares	$ (0.03)

Business Acquisition, Pro Forma Income (Loss) from Continuing Operations, Before Tax

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Business Acquisition, Pro Forma Net Income (Loss) Attributable Parent

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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-Section 50
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