Income Tax - Deferred Tax Assets and Liabilities (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Tax loss carryforwards and investment credits	$ 908	$ 658
Less unrecognized tax benefit	(238)	(229)
Tax loss carryforward net of unrecognized tax benefit	670	429
Inventory valuation	15us-gaap_DeferredTaxAssetsInventory	14us-gaap_DeferredTaxAssetsInventory
Impairment and restructuring charges	16	63
Fixed asset depreciation in arrears	39	58
Capitalized development costs	63	45
Receivables for government funding	13	22
Tax credits granted on past capital investments	1,147	1,131
Pension service costs	82	66
Stock awards	5	2
Commercial accruals	15	10
Other temporary differences	78us-gaap_DeferredTaxAssetsOther	70us-gaap_DeferredTaxAssetsOther
Total deferred tax assets	2,143us-gaap_DeferredTaxAssetsGross	1,910us-gaap_DeferredTaxAssetsGross
Valuation allowances	(1,607)	(1,454)
Deferred tax assets, net	536us-gaap_DeferredTaxAssetsNet	456us-gaap_DeferredTaxAssetsNet
Accelerated fixed asset depreciation	(26)	(58)
Acquired intangible assets	(11)	(11)
Advances of government funding	(23)	(35)
Other temporary differences	(3)us-gaap_DeferredTaxLiabilitiesOther	(13)us-gaap_DeferredTaxLiabilitiesOther
Deferred tax liabilities	(63)us-gaap_DeferredTaxLiabilities	(117)us-gaap_DeferredTaxLiabilities
Net deferred income tax asset	$ 473us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 339us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred Tax Assets Capitalized Development Costs

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Unrecognized Tax Benefits Against Existing Net Operating Losses

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Unrecognized tax benefits resulting in net operating losses carryforward.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences derived regulatory assets and liabilities.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from pension benefits.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from other provisions, reserves, allowances, and accruals not separately disclosed.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from other reserves and accruals not separately disclosed.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from restructuring reserve.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences net of deferred tax asset attributable to deductible temporary differences and carryforwards after valuation allowances.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences not separately disclosed.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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Amount of deferred tax liability attributable to taxable temporary differences from regulatory assets.

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