Activity Related to Noncontrolling Interests (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	$ 1	$ (65)
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance at beginning of period	14	80
Dividends attributable to noncontrolling interests	0	0
Net income attributable to noncontrolling interests	0	0
Balance at end of period	$ 15	$ 15

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

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 210.5-02.31)

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

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-Number 210

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

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- Definition

Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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

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-Topic 810

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-Section 45

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-Topic 810

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- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

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

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Amount of cash outflow in the form of ordinary dividends provided by the non-wholly owned subsidiary to noncontrolling interests.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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

-Publisher FASB

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-Topic 230

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