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.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Goodwill - Narrative (Details) $ in Millions		3 Months Ended			9 Months Ended		12 Months Ended
Goodwill - Narrative (Details) $ in Millions	Mar. 27, 2020 USD ($)	Sep. 25, 2020 USD ($)	Mar. 27, 2020 USD ($)	Sep. 27, 2019 USD ($)	Sep. 25, 2020 USD ($)	Sep. 27, 2019 USD ($)	Dec. 31, 2019 USD ($) reporting_unit
Goodwill [Line Items]
Number of reporting units \| reporting_unit							5
Impairment of goodwill		$ 0.0	$ 85.3	$ 0.0	$ 85.3	$ 0.0
Goodwill	$ 238.8	$ 1,058.7	$ 238.8		$ 1,058.7		$ 1,157.8
Telematics
Goodwill [Line Items]
Percentage of fair value in excess of carrying amount (as a percent)							5.00%
Impairment of goodwill	$ 85.3