Commitments and Contingencies - Changes in Accrued Environmental Remediation and Related Costs (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Environmental Remediation Obligations [Abstract]
Balance at the beginning of the year	$ 120.4
Additions charged to expense, net	2.9
Payments, net	(0.5)
Currency and other	0.1
Balance at the end of period	122.9
Amounts recognized in our Condensed Consolidated Balance Sheet at the end of the period:
Current liabilities		$ 14.4	$ 11.7
Noncurrent liabilities		108.5	108.7
Total	$ 120.4	$ 122.9	$ 120.4