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Income Taxes - Summary of Income Tax Rate (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Contingency [Line Items]
Valuation allowance released		$ 4us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount	$ 21us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount	$ 89us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount
Charges recorded in income tax expenses related to Austrian tax reform		32us-gaap_IncomeTaxReconciliationTaxContingenciesForeign
Tax benefit as a result of Mexican flat tax	36us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate
Tax credits covering years			2008 and 2009
Internal Revenue Service [Member]
Income Tax Contingency [Line Items]
Tax benefit with a settlement of claims a result of research and development tax credits			$ 36us-gaap_IncomeTaxReconciliationTaxSettlementsOther / us-gaap_IncomeTaxAuthorityNameAxis = us-gaap_InternalRevenueServiceIRSMember

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Income Tax Credit Covering Periods

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319



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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in foreign income tax contingency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 740

-SubTopic 10

-Section 50

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-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319



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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other income tax settlements.

+ References

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

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