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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, 2012	Dec. 31, 2011
Income Taxes [Line Items]
Balance, beginning of year	$ 252	$ 257
Additions based on tax positions related to current year	68	14
(Reductions)/additions based on tax positions of prior years	(31)	13
Settlements	(10)	(12)
Statute expirations	(5)	(16)
Foreign currency translation	5	(4)
Balance, ending of year	$ 279	$ 252

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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

The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

+ 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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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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