Goodwill and Other Intangible Assets - Goodwill (Details) $ in Millions	6 Months Ended
	Jun. 30, 2017 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 894.6
Foreign currency translation	13.2
Ending balance	907.8
Audio
Goodwill [Roll Forward]
Beginning balance	708.7
Foreign currency translation	13.3
Ending balance	722.0
Precision Devices
Goodwill [Roll Forward]
Beginning balance	185.9
Foreign currency translation	(0.1)
Ending balance	$ 185.8