Debt - Schedule of Long Term Debt by Maturity (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Debt Disclosure [Abstract]
2014	$ 53
2015
2016	1
2017	900
2018	550
Thereafter	8,280
Total Debt, excluding discounts	$ 9,784	$ 12,411

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Face (par) amount of debt instrument at time of issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

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- Definition

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.

+ References

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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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- Definition

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

+ References

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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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- Definition

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

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