Employee Retirement Benefits (Schedule of Expected Benefit Payments) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Pension Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2013	$ 40
2014	44
2015	49
2016	54
2017	59
2018 - 2022	405
Other Postretirement Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2013	8
2014	8
2015	9
2016	9
2017	10
2018 - 2022	64
Medicare Part D Subsidy [Abstract]
2013	1
2014	1
2015	1
2016	1
2017	1
2018-2022	$ 6

Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

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Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of the prescription drug subsidy receipts to be received after the fifth fiscal year following the latest fiscal year.

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 60

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

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

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Amount of the prescription drug subsidy receipts to be received in the next fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the fourth fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the third fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the second fiscal year following the latest fiscal year.

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