Schedule I Maturities of Commercial Paper and Long-Term Debt (Details) (Parent [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2013
Parent [Member]
Debt Instrument [Line Items]
2014	$ 1,935
2015	1,055
2016	1,134
2017	1,260
2018	1,116
Thereafter	$ 10,239

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Amount of long-term debt of the registrant maturing in the third fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04.(a))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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Amount of long-term debt of the registrant maturing after the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt of the registrant maturing in the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt of the registrant maturing in the fourth fiscal year following the latest fiscal year.

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Amount of long-term debt of the registrant maturing in the second fiscal year following the latest fiscal year.

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Amount of long-term debt of the registrant maturing in the next fiscal year following the latest fiscal year.

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