Supplemental balance sheet information - Schedule of Goodwill (Detail) $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($)
Goodwill [Roll Forward]
Goodwill, Beginning Balance	$ 2,280.8
Purchase price adjustments	7.0
Other adjustments	(0.5)
Foreign exchange	(24.1)
Goodwill, Ending Balance	2,263.2
USA
Goodwill [Roll Forward]
Goodwill, Beginning Balance	1,802.3
Purchase price adjustments	7.0
Other adjustments	0.0
Foreign exchange	0.0
Goodwill, Ending Balance	1,809.3
EMEA
Goodwill [Roll Forward]
Goodwill, Beginning Balance	8.4
Purchase price adjustments	0.0
Other adjustments	0.0
Foreign exchange	(0.6)
Goodwill, Ending Balance	7.8
Canada
Goodwill [Roll Forward]
Goodwill, Beginning Balance	441.1
Purchase price adjustments	0.0
Other adjustments	0.0
Foreign exchange	(19.0)
Goodwill, Ending Balance	422.1
LATAM
Goodwill [Roll Forward]
Goodwill, Beginning Balance	29.0
Purchase price adjustments	0.0
Other adjustments	(0.5)
Foreign exchange	(4.5)
Goodwill, Ending Balance	$ 24.0

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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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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