Restructuring and Other - Schedule of Changes in the Restructuring and MEPP Reserves (Detail) $ in Millions	6 Months Ended
	Jun. 30, 2019 USD ($)
Restructuring Cost And Reserve [Line Items]
Balance at the beginning	$ 55.2
Restructuring and Other Charges	33.0
Foreign Exchange and Other	0.2
Cash Paid	(26.0)
Balance at the end	62.4
Employee terminations
Restructuring Cost And Reserve [Line Items]
Balance at the beginning	4.8
Restructuring and Other Charges	18.9
Foreign Exchange and Other	(1.3)
Cash Paid	(15.1)
Balance at the end	7.3
Other
Restructuring Cost And Reserve [Line Items]
Balance at the beginning	6.2
Restructuring and Other Charges	12.7
Foreign Exchange and Other	1.5
Cash Paid	(7.7)
Balance at the end	12.7
MEPP withdrawal obligations
Restructuring Cost And Reserve [Line Items]
Balance at the beginning	44.2
Restructuring and Other Charges	1.4
Foreign Exchange and Other	0.0
Cash Paid	(3.2)
Balance at the end	$ 42.4