Income Taxes (Details 6) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Summary of the changes in gross unrecognized tax benefits
Balance, beginning of year	$ 257	$ 243
Additions based on tax positions related to current year	14	11
Additions based on tax positions of prior years	13	19
Settlements	(12)	(19)
Statute expirations	(16)	(1)
Foreign currency translation	(4)	4
Balance, ending of year	$ 252	$ 257

Unrecognized tax benefits increase decrease resulting from foreign currency translation.

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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

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

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-Name FASB Interpretation (FIN)

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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.

+ References

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, 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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