Income Tax - Differences in Income Taxes Computed at Netherlands Statutory Rate and Effective Income Tax Rate (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income tax benefit (expense) computed at statutory rate	$ 534	$ (84)	$ (176)
Non-deductible, non-taxable and other permanent differences, net	(110)	(38)	(50)
Income (loss) on equity-method investments	(6)	(7)	62
Valuation allowance adjustments	(197)	(130)	(54)
Impact of prior year adjustments	10		(29)
Effects on deferred taxes of changes in enacted tax rates		1	3
Current year credits	77	94	76
Other tax and credits	2	3	(12)
Benefits from tax holidays	38	113	77
Impact of uncertain tax positions	(83)	(2)	32
Earnings of subsidiaries taxed at different rates	(316)	(131)	(78)
Income tax benefit (expense)	$ (51)	$ (181)	$ (149)

Income Tax Reconciliation Current Tax Credits.

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- Definition

Income Tax Reconciliation Impact Of Uncertain Tax Positions.

+ References

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- Definition

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

+ References

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-Name Accounting Standards Codification

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-Glossary Income Tax Expense (or 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 the equity in earnings (losses) of unconsolidated subsidiaries recorded in the period that is exempt from income taxes under enacted tax laws.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to total foreign income tax expense or benefit. The foreign income tax expense or benefit difference represents the income tax expense or benefit at applicable domestic statutory income tax rates applied to foreign earnings or loss for the period versus the foreign income tax expense or benefit calculated by applying the appropriate foreign tax rates.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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The sum of the differences between total income tax expense or benefit as reported in the Income Statement for the period 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 nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles and enacted tax laws.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the current period and the expected income tax expense or benefit computed attributable to revisions of previously reported income tax expense.

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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 income that is exempt from income tax because of [foreign] tax holidays an entity has received in the period. A foreign tax "holiday" refers to a foreign jurisdiction that attempts to attract in-coming or foreign investment by offering an exemption from income taxes for some defined period of time.

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