Goodwill and Other Identifiable Intangible Assets - Additional Information (Detail) (USD $) In Millions, unless otherwise specified				12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Purchase price adjustments [Member]	Dec. 31, 2011 Purchase price adjustments [Member]	Dec. 31, 2012 Foreign currency translation [Member]	Dec. 31, 2011 Foreign currency translation [Member]	Dec. 31, 2012 Customer contracts [Member]	Dec. 31, 2012 Customer contracts [Member] Minimum [Member]	Dec. 31, 2012 Customer contracts [Member] Maximum [Member]	Dec. 31, 2012 Non-compete agreements [Member]	Dec. 31, 2012 Non-compete agreements [Member] Minimum [Member]	Dec. 31, 2012 Non-compete agreements [Member] Maximum [Member]	Dec. 31, 2012 Supply contracts [Member]	Dec. 31, 2012 Favorable lease agreements [Member]
Goodwill And Other Intangible Assets [Line Items]
Carrying value of identifiable intangible assets increase (decrease)				$ 8.9	$ 0.8	$ 0.3	$ 0.2
Estimated useful lives, in years								10 years	10 years	15 years	3 years	3 years	12 years	10 years	3 years
Amortization expense	$ 1.9	$ 1.5	$ 1.2