Landfill and Environmental Remediation Liabilities - Changes to Landfill and Environmental Remediation Liabilities (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2013 Areas	Dec. 31, 2012	Dec. 31, 2011
Environmental Remediation Obligations [Abstract]
Increase (decrease) related to year-end review of landfill capping closure and post closure obligations included in land liabilities	$ 20	$ 15
Increase related to landfill asset impairments	23
Number of assets closed	2
Risk-free discount rate of the obligations	3.00%	1.75%	2.00%
Increase (Decrease) to operating expenses due to change in discount rate used to estimate the present value of environmental remediation obligations	$ 18	$ 3

Rate applied to the undiscounted amount of environmental loss contingencies to arrive at the present value recorded as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.Y.Q1)

-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

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-Number Topic 5

-Section Y

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

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Net Increase or Decrease in the asset retirement obligation during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

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Amount of the Increase or Decrease in the amount of the asset retirement obligation during the current period for changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

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-Section 50

-Paragraph 1

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Increase (decrease) to operating expenses due to change in discount rate used to estimate present value of environmental remediation obligations.

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Number Of Capital Lease Assets Retired

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