Acquisitions and Divestitures - Additional Information (Detail) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012 Entity	Dec. 31, 2011 Entity	Dec. 31, 2010 Entity
Significant Acquisitions and Disposals [Line Items]
Number of acquisitions completed									41	45	33
Goodwill	$ 147,156,000				$ 342,486,000				$ 147,156,000	$ 342,486,000	$ 203,003,000
Tax deductible goodwill amount	80,400,000				50,600,000				80,400,000	50,600,000	49,600,000
Intangibles	150,149,000				206,775,000				150,149,000	206,775,000	113,632,000
Indefinite lived intangible assets, permits	22,700,000								22,700,000
Acquisition expenses	1,707,000	2,467,000	2,207,000	1,539,000	2,310,000	3,195,000	5,261,000	5,938,000	7,920,000	16,704,000
Estimated revenues from acquisitions									60,100,000
Proceeds from sale of business and other assets									764,000	2,371,000	8,000,000
Loss on sale of business									4,867,000	19,000	(2,955,000)
Customer relationships
Significant Acquisitions and Disposals [Line Items]
Intangibles assets, amortizable	124,700,000								124,700,000
Customer relationships | Minimum
Significant Acquisitions and Disposals [Line Items]
Finite lived intangible assets useful life									15 years
Customer relationships | Maximum
Significant Acquisitions and Disposals [Line Items]
Finite lived intangible assets useful life									40 years
Tradenames
Significant Acquisitions and Disposals [Line Items]
Intangibles assets, amortizable	2,600,000								2,600,000
Tradenames | Minimum
Significant Acquisitions and Disposals [Line Items]
Finite lived intangible assets useful life									10 years
Tradenames | Maximum
Significant Acquisitions and Disposals [Line Items]
Finite lived intangible assets useful life									15 years
Other Intangible Assets
Significant Acquisitions and Disposals [Line Items]
Intangibles assets, amortizable	100,000								100,000
Finite lived intangible assets useful life									10 years
Annual
Significant Acquisitions and Disposals [Line Items]
Estimated revenues from acquisitions									145,600,000
United States
Significant Acquisitions and Disposals [Line Items]
Number of acquisitions completed									17	21	13
Goodwill period increase decrease									109,900,000
International
Significant Acquisitions and Disposals [Line Items]
Goodwill period increase decrease									$ 37,300,000
International
Significant Acquisitions and Disposals [Line Items]
Number of acquisitions completed									24
Brazil
Significant Acquisitions and Disposals [Line Items]
Number of acquisitions completed									1	4	3
Business acquisition, ownership percentage acquired	100.00%								100.00%
Chile
Significant Acquisitions and Disposals [Line Items]
Number of acquisitions completed									3	1	1
Business acquisition, ownership percentage acquired	90.00%								90.00%