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Restructuring and Other Charges - Activity and Reserve Balances for Restructuring Charges (Parenthetical) (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Restructuring Cost and Reserve [Line Items] |  |  |  |
Asset retirement obligations | $ 4 | $ 45 | $ 4 | $ 45
Restructuring and other charges | $ 18 | 66 | 134 | 460
Pension And Other Postretirement Benefits Costs Charged To Restructuring [Member] |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Other layoff cost including reclassification in pension cost |  |  |  | 28
Environmental Remediation [Member] |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and other charges |  |  |  | 29
Pension Benefits [Member] |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Other layoff cost including reclassification in pension cost |  |  | 14 |
Restructuring and other charges |  | $ 2 | $ 2 | $ 2

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- Definition The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Asset Retirement Obligation -URI http://asc.fasb.org/extlink&oid=6505190 + Details
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