Segment and Related Information - Schedule of Segment Reporting Information to Consolidated Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Schedule Of Assets By Segment [Line Items]
Consolidated assets	$ 15,938	$ 17,447
Cash and cash equivalents	1,113	1,358
LIFO reserve	(307)	(306)
Corporate fixed assets, net	8,327	9,138
Corporate goodwill	989	989
Deferred income taxes	301
Operating Segments [Member]
Schedule Of Assets By Segment [Line Items]
Consolidated assets	13,813	14,798
Intersegment Eliminations [Member]
Schedule Of Assets By Segment [Line Items]
Consolidated assets	(271)	(299)
Other [Member]
Schedule Of Assets By Segment [Line Items]
Cash and cash equivalents	1,113	1,358
LIFO reserve	(307)	(306)
Corporate fixed assets, net	520	520
Corporate goodwill	146	148
Deferred income taxes	563	814
Other	$ 361	$ 414

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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 and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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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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