Goodwill and Other Intangible Assets - Changes in Carrying Value of Goodwill by Reportable Segment (Parenthetical) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2019	Apr. 03, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Goodwill	$ 1,231.8		$ 1,231.8		$ 1,297.1
Impairment charges	0.0		64.0
Jefferson Wells
Goodwill [Roll Forward]
Goodwill	55.5		55.5
Americas | United States
Goodwill [Roll Forward]
Goodwill	485.2		485.2		476.5
Americas | United States | Jefferson Wells
Goodwill [Roll Forward]
Goodwill	540.7		540.7		532.0
Southern Europe
Goodwill [Roll Forward]
Goodwill				$ 33.8
Southern Europe | France
Goodwill [Roll Forward]
Goodwill	65.5		65.5		68.9
Southern Europe | Italy
Goodwill [Roll Forward]
Goodwill	4.5		4.5		4.8
Northern Europe | Germany
Goodwill [Roll Forward]
Goodwill	$ 64.8		$ 64.8		$ 129.2
Impairment charges		$ 60.2
APME | New Zealand
Goodwill [Roll Forward]
Impairment charges		$ 3.8