Income Taxes (Net Deferred Income Tax Assets and Liabilities) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred income tax assets related to
Employee benefits	$ 877	$ 706
Contingent and accrued liabilities	671	613
Operating loss and other carry-forwards	380	269
Inventories	24us-gaap_DeferredTaxAssetsInventory	31us-gaap_DeferredTaxAssetsInventory
Property	29	4
Derivatives	24	0
Other	99us-gaap_DeferredTaxAssetsOther	47us-gaap_DeferredTaxAssetsOther
Valuation allowance	(181)	(136)
Total	1,923us-gaap_DeferredTaxAssetsNet	1,534us-gaap_DeferredTaxAssetsNet
Deferred income tax liabilities related to
Property	401	310
Intangibles	805	450
Employee benefits	69	55
Deferred Tax Liabilities, Derivatives	0	41
Deferred Tax Liabilities, Undistributed Foreign Earnings	263
Other	180us-gaap_DeferredTaxLiabilitiesOther	21us-gaap_DeferredTaxLiabilitiesOther
Total	1,718us-gaap_DeferredTaxLiabilities	877us-gaap_DeferredTaxLiabilities
Deferred income tax assets – net	$ 205us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 657us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred Tax Liabilities, Compensation and Benefits

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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 from intangible assets including goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiaries and other recognized entities not within the country of domicile of the entity.

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