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Financial Instruments - Additional Information (Detail) | 12 Months Ended |  |  |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |
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Dec. 31, 2012 USD ($) | Dec. 31, 2011 USD ($) | Dec. 31, 2012 Asset-backed Securities [Member] USD ($) | Dec. 31, 2012 Asset-backed Securities [Member] CAD | Dec. 31, 2011 Asset-backed Securities [Member] USD ($) | Dec. 31, 2011 Asset-backed Securities [Member] CAD | Dec. 31, 2012 CANADA Gigajoule | Dec. 31, 2012 CANADA Minimum [Member] | Dec. 31, 2012 CANADA Maximum [Member] | Dec. 31, 2012 UNITED STATES MMBTU | Dec. 31, 2012 UNITED STATES Minimum [Member] | Dec. 31, 2012 UNITED STATES Maximum [Member] | Dec. 31, 2012 Natural Gas Swap Contracts [Member] USD ($) | Dec. 31, 2012 Forward Contracts [Member] USD ($) | Dec. 31, 2012 Propylene Contracts [Member] USD ($) lb | Dec. 31, 2012 Propylene Contracts [Member] Minimum [Member] USD ($) | Dec. 31, 2012 Propylene Contracts [Member] Maximum [Member] USD ($)
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Foreign exchange forward contracts, gain recognized in other comprehensive income |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 69,000,000 |  |  |
Foreign exchange forward contracts, loss recognized in other comprehensive income |  |  |  |  |  |  |  |  |  |  |  |  | 4,000,000 | 20,000,000 |  |  |
Swaps outstanding fixed price |  |  |  |  |  |  | 700,000 |  |  | 500,000 |  |  |  |  | 18,100,000 |  |
Swap fixed price |  |  |  |  |  |  |  | 6.28 | 6.50 |  | 6.88 | 7.06 |  |  |  |  |
Fixed price per lbs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.5375 | 0.6500
Unrealized gains on contracts |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,000,000 |  |
Face value of investments |  |  |  | 107,000,000 |  | 125,000,000 |  |  |  |  |  |  |  |  |  |  |
Trading securities | 1,612,000,000 | 1,407,000,000 | 90,000,000 | 90,000,000 | 82,000,000 | 84,000,000 |  |  |  |  |  |  |  |  |  |  |
Fair value of investments carrying value | 9,000,000 | 12,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt due within one year | $ 249,000,000 | $ 151,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of sales to six largest customers | 83.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition The effective portion of gains on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44C -Subparagraph b -Clause 2 -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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -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. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 + Details
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- Definition Carrying amount of long-term debt, net of unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19,20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Article 5 + Details
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- Definition The total of financial instruments that are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) or for debt and equity securities formerly categorized as available-for-sale or held-to-maturity which the entity held as of the date it opted to account for such securities at fair value. An enterprise may also categorize such a security as trading without the intent to sell it in the near term assuming the decision to categorize the security as trading occurred at acquisition. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13 -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. Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph a -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. Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 159 -Paragraph 29 -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. Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Implementation Guide (Q and A) -Number FAS115 -Paragraph 35 -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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