v2.4.0.6

Income Taxes - Reconciliation of Beginning and Ending Unrecognized Tax Benefits (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reconciliation Of Unrecognized Tax Benefits [Line Items]
Unrecognized Tax Benefits, Beginning Balance	$ 1,125	$ 1,208	$ 1,068
Additions based on tax positions related to the current year	46	63	18
Additions for tax positions of prior years	145	344	177
Reductions for tax positions of prior years	(35)	(199)	(33)
Settlements	(206)	(215)	(19)
Lapse of statute	(4)	(76)	(3)
Unrecognized Tax Benefits, Ending Balance	$ 1,071	$ 1,125	$ 1,208

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

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The gross amount of decreases 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 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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