Landfill and Environmental Remediation Liabilities - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014
Environmental Remediation Obligations [Abstract]
Anticipated payments for currently identified environmental remediation liabilities, in 2015	$ 43
Anticipated payments for currently identified environmental remediation liabilities, in 2016	26
Anticipated payments for currently identified environmental remediation liabilities, in 2017	26
Anticipated payments for currently identified environmental remediation liabilities, in 2018	24
Anticipated payments for currently identified environmental remediation liabilities, in 2019	12
Anticipated payments for currently identified environmental remediation liabilities, after 2019	$ 98

Undiscounted amount of the accrual for environmental loss contingencies maturing after the fifth fiscal year following the latest fiscal year.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section Y

-Paragraph Question 1

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- Definition

Undiscounted amount of the accrual for environmental loss contingencies maturing in the fifth fiscal year following the latest fiscal year.

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- Definition

Undiscounted amount of the accrual for environmental loss contingencies maturing in the fourth fiscal year following the latest fiscal year.

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- Definition

Undiscounted amount of the accrual for environmental loss contingencies maturing in the second fiscal year following the latest fiscal year.

+ References

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- Definition

Undiscounted amount of the accrual for environmental loss contingencies maturing in the third fiscal year following the latest fiscal year.

+ References

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- Definition

Undiscounted amount of the accrual for environmental loss contingencies maturing in the next fiscal year following the latest fiscal year.

+ References

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