Acquisitions - Additional Information (Detail) - Southern Waste Systems [Member] $ in Millions	Jan. 08, 2016 USD ($)
Business Acquisition [Line Items]
Total consideration, net of cash acquired, for business acquisitions closed during the year	$ 525
Allocation of consideration to property and equipment	93
Allocation of consideration to other intangible assets	182
Allocation of consideration to goodwill	$ 250