Landfill and Environmental Remediation Liabilities (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2011	Dec. 31, 2010
Landfill and Environmental Remediation Liabilities (Textual) [Abstract]
Fair value of trust funds and escrow accounts	$ 121	$ 121
Carrying value of restricted trust funds and escrow accounts for which company is the not sole beneficiary specifically for future settlement of landfill and environmental remediation liabilities	108	108
Risk-free discount rate of the obligations	2.00%	2.00%	3.50%
Accrual for environmental loss contingencies material changes in accrual from change in discount rate	25	25
Favorable revision to remediation liability at closed site to partially offset the charge		$ 9

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 SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section Y

-Paragraph Question 1

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 96-1

-Paragraph 161, 132

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Accrual for environmental loss contingencies material changes in accrual from change in discount rate.

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- Definition

Carrying Value of Restricted Trust Funds and Escrow Accounts for Which the Company is Not the Sole Beneficiary Specifically for Future Settlement of Landfill and Environmental Remediation Liabilities.

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Fair Value of Restricted Trust Funds and Escrow Accounts for which the company is the sole beneficiary, specifically for future settlement of landfill and environmental remediation liabilities.

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Favorable revision to remediation liability at closed site to partially offset the charge.

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- Definition

Landfill and Environmental Remediation Liabilities.

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