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Income Taxes - Summary of Changes in Gross Unrecognized Tax Benefits (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Balance, beginning of year	$ 279	$ 252	$ 257
Additions based on tax positions related to current year	35	68	14
(Reductions)/additions based on tax positions of prior years	(44)	(31)	13
Settlements	(24)	(10)	(12)
Statute expirations	(7)	(5)	(16)
Foreign currency translation	(1)	5	(4)
Balance, ending of year	$ 238	$ 279	$ 252

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- Definition

Unrecognized tax benefits increase decrease resulting from foreign currency translation.

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Unrecognized Tax Benefits Increase Decreases Resulting From Prior Period Tax Positions

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854



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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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