Landfill and Environmental Remediation Liabilities - Changes to Landfill and Environmental Remediation Liabilities (Parenthetical) (Detail) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Deffenbaugh Disposal, Inc. [Member]
Environmental Exit Cost [Line Items]
Increase (Decrease) in landfill liabilities	$ 18
Wheelabrator [Member]
Environmental Exit Cost [Line Items]
Increase (Decrease) in landfill liabilities		$ (25)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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