Long Term Debt (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Other debt	$ 483us-gaap_OtherLongTermDebt	$ 476us-gaap_OtherLongTermDebt
Total long-term debt	7,041	7,034
Less: unamortized discounts	(872)	(882)
Total long-term debt, net	6,169us-gaap_LongTermDebtNoncurrent	6,152us-gaap_LongTermDebtNoncurrent
2.13% to 6.15%, due 2016 to 2042
Debt Instrument [Line Items]
Notes	5,642	5,642
7.00% To 7.75%, Due 2016 To 2036
Debt Instrument [Line Items]
Notes	$ 916	$ 916

Aggregate unamortized discount on long-term debt.

No definition available.

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- Definition

Carrying amount of long-term debt, exclusive of unamortized discount or premium.

+ References

No definition available.

+ Details

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- Details

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of all notes and loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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- Definition

Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

+ Details

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- Details

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