Goodwill, Intangible and Long-Lived Assets - Summary of Changes in the Carrying Value of Goodwill by Reportable Segment (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Carrying value of goodwill by reportable operating segment
Opening balance	$ 6,956.7	$ 6,814.3	$ 1,126.9
Acquisition	14.2		5,675.2
Acquisitions		213.6
Currency and other adjustments	33.9	(71.2)	12.2
Closing balance	7,004.8	6,956.7	6,814.3
Accumulated impairment losses	19.4
The Americas Group
Carrying value of goodwill by reportable operating segment
Opening balance	2,256.6	2,555.6	285.4
Acquisition			2,276.1
Acquisitions		(273.9)
Currency and other adjustments		(25.1)	(5.9)
Closing balance	2,256.6	2,256.6	2,555.6
Accumulated impairment losses	10.5
Consumer Brands Group
Carrying value of goodwill by reportable operating segment
Opening balance	1,753.8	2,233.2	699.9
Acquisition			1,473.2
Acquisitions		(413.3)
Currency and other adjustments	0.1	(66.1)	60.1
Closing balance	1,753.9	1,753.8	2,233.2
Accumulated impairment losses	8.1
Performance Coatings Group
Carrying value of goodwill by reportable operating segment
Opening balance	2,946.3	2,025.5	141.6
Acquisition	14.2		1,925.9
Acquisitions		900.8
Currency and other adjustments	33.8	20.0	(42.0)
Closing balance	2,994.3	$ 2,946.3	$ 2,025.5
Accumulated impairment losses	$ 0.8

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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