Intangible assets - Finite-Lived and Indefinite-Lived Intangible Assets (Details) - USD ($) $ in Millions	Jun. 27, 2020	Dec. 28, 2019
Finite-Lived Intangible Assets
Finite-lived, cost	$ 2,156.1	$ 2,188.7
Finite-lived, accumulated amortization	(834.3)	(782.1)
Finite-lived, net	1,321.8	1,406.6
Indefinite-lived, cost	513.4	513.4
Indefinite-lived, accumulated impairment	(44.0)	(44.0)
Indefinite-lived, net	469.4	469.4
Cost	2,669.5	2,702.1
Accumulated amortization and impairment	(878.3)	(826.1)
Net	1,791.2	1,876.0
—Customer relationships
Finite-Lived Intangible Assets
Finite-lived, cost	1,982.0	2,021.8
Finite-lived, accumulated amortization	(702.5)	(656.3)
Finite-lived, net	1,279.5	1,365.5
—Technology
Finite-Lived Intangible Assets
Finite-lived, cost	90.4	90.8
Finite-lived, accumulated amortization	(87.9)	(87.8)
Finite-lived, net	2.5	3.0
—Capitalized software
Finite-Lived Intangible Assets
Finite-lived, cost	83.7	76.1
Finite-lived, accumulated amortization	(43.9)	(38.0)
Finite-lived, net	$ 39.8	$ 38.1

Indefinite-Lived Intangible Assets (Excluding Goodwill), Gross

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Indefinite-Lived Intangible Assets (Excluding Goodwill), Impaired, Accumulated Impairment Loss

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- Definition

Intangible Assets (Excluding Goodwill), Accumulated Amortization and Impairment Loss

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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