Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011 Y	Dec. 31, 2010
Income Taxes [Line Items]
Tax benefit included in discontinued operations		$ 1	$ 3
Tax benefit realized from exercise of employee stock options	1	6	2
Unamortized tax-deductible goodwill resulting from intercompany stock sales and reorganizations	97
Minimum unamortized tax-deduction rate on goodwill	30.00%
Maximum unamortized tax-deduction rate on goodwill	34.00%
Noncash charge related to elimination of a deferred tax asset			79
Percentage of temporary tax differences that reverse within the carryforward period	25.00%
Percentage of temporary tax differences that reverse within tax planning strategies	5.00%
Percentage of deferred tax asset exclusive of reversing temporary differences	70.00%
Holiday period, years		10
Measurement of net deferred tax asset and noncash charge to earnings		60
Decrease to the net deferred tax asset and noncash charge to earnings		120
Income tax benefit for operational losses related to certain foreign jurisdictions that are excluded from the estimated annual effective tax rate calculation	8,000
Percentage of the effect of unrecognized tax benefit, if recorded	6.00%	2.00%	4.00%
Interest and penalties recognized	3	2	1
Income related to accrued interest and penalties	7	2	4
Amount accrued for payment of interest and penalties	$ 15	$ 12

Decrease In Net Deferred Tax Asset And Noncash Charge To Earnings

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Income tax expense, payment of interest and penalties.

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Income Tax Holiday, Holiday Period

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Maximum unamortized tax deduction rate on goodwill.

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Measurement Of Net Deferred Tax Asset And Noncash Charge To Earnings

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Minimum unamortized tax deduction rate on goodwill.

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Percentage of deferred tax asset exclusive of reversing temporary differences.

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Percentage of the effect of unrecognized tax benefit, if recorded.

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Percentage of temporary tax differences that reverse within the carryforward period.

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Percentage of temporary tax differences that reverse within tax planning strategies.

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Unamortized tax deductible goodwill resulting from intercompany stock sales and reorganizations.

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Tax benefit from provision recognizing a loss for initial, or subsequent, write-down to fair value (less cost to sell) of a of a disposal group that is classified as a component of the entity, which remains unsold as of the reporting date. May include a tax on the (gain) for the recognition of a subsequent increase in fair value (less cost to sell), but not in excess of the cumulative loss previously recognized through write-downs.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

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The sum of other amounts reflected in the reconciliation of the statutory tax provision (benefit) to the actual tax provision (benefit).

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to changes in foreign income tax contingencies, whether recorded or adjusted, during the period.

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This element represents the amount of statutory penalties accrued as of the date of the statement of financial position for a tax position claimed or expected to be claimed by the entity, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties.

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