Amortization Expense and Contra-Expense Associated with Intangible Assets and Liabilities (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012
Waste and Service Contracts (Contra-Expense)
Expected Amortization Expense [Line Items]
Three Months ended March 31, 2012	$ (3)
Remainder of 2012	(9)
2013	(12)
2014	(13)
2015	(8)
2016	(8)
Thereafter	(23)
Total	(73)
Waste, Service and Energy Contracts (Amortization Expense)
Expected Amortization Expense [Line Items]
Three Months ended March 31, 2012	9
Remainder of 2012	26
2013	32
2014	29
2015	26
2016	23
Thereafter	289
Total	$ 425