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The total amount of unrecognized tax benefits that, if recognized, would be in the form of tax credits and net operating loss carryforwards that would attract a full valuation allowance.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the estimated loss from legal settlements.

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Tax year being audited in the income tax examination, in CCYY format.

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The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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Amount of (increase) decrease reasonably possible in the estimated lower bound of the unrecognized tax benefit for a tax position taken or expected to be taken.

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Amount of (increase) decrease reasonably possible in the estimated upper bound of the unrecognized tax benefit for a tax position taken or expected to be taken.

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of interest expense accrued for an underpayment of income taxes.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended			3 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014	Dec. 31, 2011
Income Tax Disclosure [Line Items]
Unrecognized tax benefits	$ 1,687,000,000us-gaap_UnrecognizedTaxBenefits	$ 147,000,000us-gaap_UnrecognizedTaxBenefits	$ 46,000,000us-gaap_UnrecognizedTaxBenefits		$ 31,000,000us-gaap_UnrecognizedTaxBenefits
Deferred tax benefit	(147,000,000)us-gaap_DeferredIncomeTaxExpenseBenefit	137,000,000us-gaap_DeferredIncomeTaxExpenseBenefit	159,000,000us-gaap_DeferredIncomeTaxExpenseBenefit
Tronox-related contingent loss	4,360,000,000us-gaap_LossContingencyLossInPeriod	850,000,000us-gaap_LossContingencyLossInPeriod	(250,000,000)us-gaap_LossContingencyLossInPeriod
Uncertain tax position	1,568,000,000	72,000,000	1,000,000
Unrecognized tax benefits that would affect the effective tax rate on income if recognized	1,456,000,000
Unrecognized tax benefits that would be in the form of tax credits and net operating loss carryforwards	188,000,000
The lower range of unrecognized tax benefits expected to reverse within the next 12 months due to expiration of statutes of limitation and audit settlements	120,000,000
The higher range of unrecognized tax benefits expected to reverse within the next 12 months due to expiration of statutes of limitation and audit settlements	130,000,000
Accrued interest related to uncertain tax positions	9,000,000	8,000,000
Interest and penalties recognized in income tax expense (benefit)	1,000,000	(20,000,000)
Internal Revenue Service (IRS) [Member] \| Earliest Tax Year [Member]
Income Tax Disclosure [Line Items]
Tax year currently under routine examination	2008
Internal Revenue Service (IRS) [Member] \| Latest Tax Year [Member]
Income Tax Disclosure [Line Items]
Tax year currently under routine examination	2014
Portion Of Unrecognized Tax Benefits With Highly Certain Deductibility [Member]
Income Tax Disclosure [Line Items]
Unrecognized tax benefits	1,679,000,000
Portion Of Unrecognized Tax Benefits With Highly Certain Deductibility And Uncertain Timing [Member]
Income Tax Disclosure [Line Items]
Unrecognized tax benefits	8,000,000
Tronox Litigation [Member] \| Pending Litigation [Member]
Income Tax Disclosure [Line Items]
Deferred tax benefit	(316,000,000)	(274,000,000)
Tronox-related contingent loss	4,360,000,000	850,000,000		4,300,000,000
Total deferred tax benefit related to the Tronox-related contingent liability	590,000,000	0
Uncertain tax position	1,326,000,000
Additions [Member]
Income Tax Disclosure [Line Items]
Increase in valuation allowances	59,000,000	38,000,000	426,000,000
Reductions [Member]
Income Tax Disclosure [Line Items]
Increase in valuation allowances	(13,000,000)	(142,000,000)	(59,000,000)
Changes in Judgment Regarding Future Realizability of Deferred Tax Assets [Member]
Income Tax Disclosure [Line Items]
Increase in valuation allowances	0
Changes in Judgment Regarding Future Realizability of Deferred Tax Assets [Member] \| Additions [Member]
Income Tax Disclosure [Line Items]
Increase in valuation allowances		$ 2,000,000	$ 23,000,000