Income Taxes - Deferred Tax Assets and Liabilities, Net (Detail) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Deferred income taxes	$ 59	$ 2,653
Deferred income taxes (long-term liability)	(1,144)	(1,334)
Net Deferred Tax Liabilities	$ (1,085)
Net Deferred Tax Assets		$ 1,319

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32537-109319

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32537-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=75116654&loc=d3e31931-109318

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, with jurisdictional netting and classified as noncurrent.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=75116654&loc=d3e31931-109318

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