Goodwill and Identifiable Intangible Assets - Schedule of Goodwill (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,271.2
Purchase Accounting Adjustments	(0.2)
Foreign currency translation	(29.4)
Goodwill, ending balance	1,241.6
Performance Coatings [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	1,189.2
Purchase Accounting Adjustments	(0.2)
Foreign currency translation	(27.5)
Goodwill, ending balance	1,161.5
Transportation Coatings [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	82.0
Purchase Accounting Adjustments	0.0
Foreign currency translation	(1.9)
Goodwill, ending balance	$ 80.1