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Financial Instruments - Foreign Exchange Forward Contracts Representing Commitments to Buy and Sell Various Foreign Currencies (Detail) In Millions, unless otherwise specified |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended
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Dec. 31, 2012 Canadian Dollar [Member] USD ($) | Dec. 31, 2012 Canadian Dollar [Member] EUR (€) | Dec. 31, 2012 Canadian Dollar [Member] 2013 [Member] USD ($) | Dec. 31, 2012 Canadian Dollar [Member] 2013 [Member] EUR (€) | Dec. 31, 2012 Canadian Dollar [Member] 2013 [Member] U S Dollar [Member] | Dec. 31, 2012 Canadian Dollar [Member] 2013 [Member] Euros [Member] | Dec. 31, 2012 Canadian Dollar [Member] 2014 [Member] USD ($) | Dec. 31, 2012 Canadian Dollar [Member] 2014 [Member] EUR (€) | Dec. 31, 2012 Canadian Dollar [Member] 2014 [Member] U S Dollar [Member] | Dec. 31, 2012 Canadian Dollar [Member] 2014 [Member] Euros [Member] | Dec. 31, 2012 Canadian Dollar [Member] 2015 [Member] USD ($) | Dec. 31, 2012 Canadian Dollar [Member] 2015 [Member] EUR (€) | Dec. 31, 2012 Canadian Dollar [Member] 2015 [Member] U S Dollar [Member] | Dec. 31, 2012 Canadian Dollar [Member] 2016 [Member] USD ($) | Dec. 31, 2012 Canadian Dollar [Member] 2016 [Member] EUR (€) | Dec. 31, 2012 Canadian Dollar [Member] 2016 [Member] U S Dollar [Member] | Dec. 31, 2012 U S Dollar [Member] MXN | Dec. 31, 2012 U S Dollar [Member] 2013 [Member] MXN | Dec. 31, 2012 U S Dollar [Member] 2013 [Member] Mexican Peso [Member] | Dec. 31, 2012 U S Dollar [Member] 2014 [Member] MXN | Dec. 31, 2012 U S Dollar [Member] 2014 [Member] Mexican Peso [Member] | Dec. 31, 2012 U S Dollar [Member] 2015 [Member] MXN | Dec. 31, 2012 U S Dollar [Member] 2015 [Member] Mexican Peso [Member] | Dec. 31, 2012 U S Dollar [Member] 2016 [Member] MXN | Dec. 31, 2012 Euros [Member] USD ($) | Dec. 31, 2012 Euros [Member] CZK | Dec. 31, 2012 Euros [Member] GBP (£) | Dec. 31, 2012 Euros [Member] PLN | Dec. 31, 2012 Euros [Member] 2013 [Member] USD ($) | Dec. 31, 2012 Euros [Member] 2013 [Member] CZK | Dec. 31, 2012 Euros [Member] 2013 [Member] GBP (£) | Dec. 31, 2012 Euros [Member] 2013 [Member] PLN | Dec. 31, 2012 Euros [Member] 2013 [Member] U S Dollar [Member] | Dec. 31, 2012 Euros [Member] 2013 [Member] British Pound [Member] | Dec. 31, 2012 Euros [Member] 2013 [Member] Czech Koruna [Member] | Dec. 31, 2012 Euros [Member] 2013 [Member] Polish Zloty [Member] | Dec. 31, 2012 Euros [Member] 2014 [Member] USD ($) | Dec. 31, 2012 Euros [Member] 2014 [Member] CZK | Dec. 31, 2012 Euros [Member] 2014 [Member] GBP (£) | Dec. 31, 2012 Euros [Member] 2014 [Member] PLN | Dec. 31, 2012 Euros [Member] 2014 [Member] U S Dollar [Member] | Dec. 31, 2012 Euros [Member] 2014 [Member] British Pound [Member] | Dec. 31, 2012 Euros [Member] 2014 [Member] Czech Koruna [Member] | Dec. 31, 2012 Euros [Member] 2014 [Member] Polish Zloty [Member] | Dec. 31, 2012 Euros [Member] 2015 [Member] USD ($) | Dec. 31, 2012 Euros [Member] 2015 [Member] CZK | Dec. 31, 2012 Euros [Member] 2015 [Member] GBP (£) | Dec. 31, 2012 Euros [Member] 2015 [Member] PLN | Dec. 31, 2012 Euros [Member] 2015 [Member] U S Dollar [Member] | Dec. 31, 2012 Euros [Member] 2015 [Member] British Pound [Member] | Dec. 31, 2012 Euros [Member] 2015 [Member] Czech Koruna [Member] | Dec. 31, 2012 Euros [Member] 2016 [Member] USD ($) | Dec. 31, 2012 Euros [Member] 2016 [Member] CZK | Dec. 31, 2012 Euros [Member] 2016 [Member] GBP (£) | Dec. 31, 2012 Euros [Member] 2016 [Member] PLN | Dec. 31, 2012 Euros [Member] 2016 [Member] U S Dollar [Member]
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Notional amount of foreign currency derivatives | $ (684) | € 74 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6,049 |  |  |  |  |  |  |  | $ (123) | 4,833 | £ 71 | 127 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate |  |  |  |  | 1.01252 | 1.31881 |  |  | 1.04151 | 1.31939 |  |  | 1.03073 |  |  | 1.03697 |  |  | 0.07313 |  | 0.06844 |  | 0.06894 |  |  |  |  |  |  |  |  |  | 0.75541 | 1.17565 | 0.03988 | 0.23344 |  |  |  |  | 0.74515 | 1.14482 | 0.03980 | 0.22452 |  |  |  |  |  | 1.19170 | 0.03971 |  |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate |  |  |  |  | 1.02054 | 1.28626 |  |  | 1.01573 |  |  |  | 1.01754 |  |  | 1.04751 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.76441 | 1.24572 | 0.04014 |  |  |  |  |  | 0.77097 |  |  |  |  |  |  |  | 0.77597 |  |  |  |  |  |  | 0.77162
Foreign exchange forward contract, Purchases |  |  | 229 | 48 |  |  | 31 | 34 |  |  | 23 |  |  | 12 |  |  |  | 3,179 |  | 2,071 |  | 799 |  |  |  |  |  |  | 53 | 2,488 | 41 | 86 |  |  |  |  | 17 | 1,572 | 31 | 41 |  |  |  |  |  | 784 | 13 |  |  |  |  |  |  |  |  |
Foreign exchange forward contract, Sales |  |  | $ (600) | € (8) |  |  | $ (271) |  |  |  | $ (104) |  |  | $ (4) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ (93) | (11) | £ (14) |  |  |  |  |  | $ (52) |  |  |  |  |  |  |  | $ (35) |  |  |  |  |  |  | $ (13) |  |  |  |

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- Definition Aggregate notional amount of foreign currency derivatives to purchase a foreign currency. Notional amount refers to the number of currency units specified in the foreign currency derivative contract. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Notional Amount -URI http://asc.fasb.org/extlink&oid=6519104 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959 + Details
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