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Contingencies and Commitments - Additional Information - 1 (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2017 | Jun. 30, 2017 | Dec. 31, 2016
Loss Contingencies [Line Items] |  |  |
Number of cleanup locations |  | More than 100 |
Remediation reserve balance | $ 301 | $ 301 | $ 308
Remediation reserve balance, classified as a current liability | 42 | 42 | 48
Payments related to remediation expenses applied against the reserve | 5 | $ 7 |
Actual remediation fieldwork period |  | 4 years |
Maximum [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Majority of the project funding period |  | 2021 |
Minimum [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Majority of the project funding period |  | 2017 |
Massena West, NY [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Remediation reserve balance | $ 224 | $ 224 | $ 228
Recurring Costs of Managing Hazardous Substances and Environmental Programs [Member] | Maximum [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Percentage of cost of goods sold |  | 1.00% |

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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 + Details
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