Commitments and Contingencies - Changes in Accrued Environmental Remediation and Related Costs (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Dec. 31, 2012
Commitments And Contingent Liabilities [Line Items]
Balance at the beginning of the year	$ 50.2
Additions charged to expense, net	13.1
Payments, net	(1.3)
Changes in currency exchange rates	(0.2)
Balance at the end of period	61.8
Amounts recognized in our Condensed Consolidated Balance Sheet at the end of the period:
Current liabilities	6.5	7.6
Noncurrent liabilities	55.3	42.6
Total	$ 61.8