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Inventories - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Inventories Net [Line Items] |  |  |
Percentage inventories valued on a last in, first out (LIFO) basis | 35.00% | 35.00% |
Total inventories valued on an average-cost basis | $ 770 | $ 801 |
Recognition of income caused by partial liquidations of the lower cost LIFO inventory base, gross | 1 | 2 | 27
Recognition of income caused by partial liquidations of the lower cost LIFO inventory base, after tax | $ 1 | $ 1 | $ 17

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- Definition Recognition of income caused by partial liquidations of the lower cost LIFO inventory base gross. + References No definition available. + Details
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- Definition Recognition of income caused by partial liquidations of lower cost LIFO inventory base net. + References No definition available. + Details
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- Definition The percentage of LIFO (last in first out) inventory to total inventory as of the balance sheet date if other than 100 percent. + References No definition available. + Details
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- Definition The amount of weighted average cost inventory present at the reporting date when inventory is valued using different valuation methods. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Section A -Paragraph 9 -Chapter 3 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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