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Segment and Geographic Area Information - Schedule of Segment Reporting Information to Consolidated Assets (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule Of Assets By Segment [Line Items]
Consolidated assets	$ 37,399us-gaap_Assets	$ 35,742us-gaap_Assets
Cash and cash equivalents	1,877us-gaap_CashAndCashEquivalentsAtCarryingValue	1,437us-gaap_CashAndCashEquivalentsAtCarryingValue	1,861us-gaap_CashAndCashEquivalentsAtCarryingValue	1,939us-gaap_CashAndCashEquivalentsAtCarryingValue
Corporate goodwill	5,247us-gaap_Goodwill	3,415us-gaap_Goodwill	5,170us-gaap_Goodwill
Corporate fixed assets, net	16,426us-gaap_PropertyPlantAndEquipmentNet	17,639us-gaap_PropertyPlantAndEquipmentNet
LIFO reserve	(767)us-gaap_InventoryLIFOReserve	(691)us-gaap_InventoryLIFOReserve
Operating Segments [Member]
Schedule Of Assets By Segment [Line Items]
Consolidated assets	31,232us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember	29,247us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Intersegment Eliminations [Member]
Schedule Of Assets By Segment [Line Items]
Consolidated assets	(490)us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember	(385)us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember
Other [Member]
Schedule Of Assets By Segment [Line Items]
Cash and cash equivalents	1,877us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember	1,437us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember
Deferred income taxes	3,175us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember	3,410us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember
Corporate goodwill	510us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember	518us-gaap_Goodwill / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember
Corporate fixed assets, net	819us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember	879us-gaap_PropertyPlantAndEquipmentNet / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember
LIFO reserve	(767)us-gaap_InventoryLIFOReserve / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember	(691)us-gaap_InventoryLIFOReserve / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember
Other	$ 1,043us-gaap_OtherAssets / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember	$ 1,327us-gaap_OtherAssets / us-gaap_ConsolidationItemsAxis = us-gaap_MaterialReconcilingItemsMember

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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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 after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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