Commitments and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified			12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 Minimum	Dec. 31, 2012 Maximum
Commitments Disclosure [Line Items]
Amount outstanding standby letters of credit	$ 29.2	$ 34.2
Warranty Maturity Periods			1 year	10 years
Reserves related to environmental remediation	$ 1.8	$ 2.2