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Financial Instruments - Foreign Exchange Forward Contracts Representing Commitments to Buy and Sell Various Foreign Currencies (Detail) | 12 Months Ended |  |
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Dec. 31, 2017 EUR (€) | Dec. 31, 2017 USD ($) | Dec. 31, 2017 GBP (£) | Dec. 31, 2017 CZK (Kč) | Dec. 31, 2016 USD ($)
Derivative [Line Items] |  |  |  |  |
Assets, Gross amounts presented in consolidated balance sheets |  | $ 101,000,000 |  |  | $ 18,000,000
Canada, Dollars | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | € | € 10,000,000 |  |  |  |
Canada, Dollars | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 1,732,000,000 |  |  |
Canada, Dollars | 2018 [Member] | US Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.27249 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.78027 |  |  |  |
Canada, Dollars | 2018 [Member] | Euro [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.48899 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.66174 |  |  |  |
Canada, Dollars | 2018 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | € 22,000,000 | 208,000,000 |  |  |
Canada, Dollars | 2018 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | € 16,000,000 | 980,000,000 |  |  |
Canada, Dollars | 2019 [Member] | US Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.29098 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.77989 |  |  |  |
Canada, Dollars | 2019 [Member] | Euro [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.56845 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.64926 |  |  |  |
Canada, Dollars | 2019 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | € 9,000,000 | 41,000,000 |  |  |
Canada, Dollars | 2019 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | € 5,000,000 | 596,000,000 |  |  |
Canada, Dollars | 2020 [Member] | US Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.29947 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.77338 |  |  |  |
Canada, Dollars | 2020 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 9,000,000 |  |  |
Canada, Dollars | 2020 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 291,000,000 |  |  |
Canada, Dollars | 2021 [Member] | US Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.78321 |  |  |  |
Canada, Dollars | 2021 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 97,000,000 |  |  |
Canada, Dollars | 2022 [Member] | US Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.78978 |  |  |  |
Canada, Dollars | 2022 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 26,000,000 |  |  |
United States of America, Dollars | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 6,109,000,000 |  |  |
United States of America, Dollars | 2018 [Member] | Mexican Peso [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.05170 |  |  |  |
United States of America, Dollars | 2018 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 3,778,000,000 |  |  |
United States of America, Dollars | 2019 [Member] | Mexican Peso [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.04678 |  |  |  |
United States of America, Dollars | 2019 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 1,755,000,000 |  |  |
United States of America, Dollars | 2020 [Member] | Mexican Peso [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.04684 |  |  |  |
United States of America, Dollars | 2020 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 576,000,000 |  |  |
Euro Member Countries, Euro | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | Kč |  |  |  | Kč 8,100,000,000 |
Euro Member Countries, Euro | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Assets, Gross amounts presented in consolidated balance sheets |  | (63,000,000) | £ (49,000,000) |  |
Euro Member Countries, Euro | 2018 [Member] | US Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.86349 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.17146 |  |  |  |
Euro Member Countries, Euro | 2018 [Member] | British Pound [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.11963 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.83230 |  |  |  |
Euro Member Countries, Euro | 2018 [Member] | Czech Koruna [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.03791 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 25.46600 |  |  |  |
Euro Member Countries, Euro | 2018 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 104,000,000 | 7,000,000 | 4,128,000,000 |
Euro Member Countries, Euro | 2018 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 130,000,000 | 28,000,000 | 14,000,000 |
Euro Member Countries, Euro | 2019 [Member] | US Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.86276 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.18414 |  |  |  |
Euro Member Countries, Euro | 2019 [Member] | British Pound [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.11072 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.83346 |  |  |  |
Euro Member Countries, Euro | 2019 [Member] | Czech Koruna [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.03799 |  |  |  |
Euro Member Countries, Euro | 2019 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 37,000,000 | 1,000,000 | 2,885,000,000 |
Euro Member Countries, Euro | 2019 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 68,000,000 | 14,000,000 |  |
Euro Member Countries, Euro | 2020 [Member] | US Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.85860 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.22742 |  |  |  |
Euro Member Countries, Euro | 2020 [Member] | British Pound [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.88220 |  |  |  |
Euro Member Countries, Euro | 2020 [Member] | Czech Koruna [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.03851 |  |  |  |
Euro Member Countries, Euro | 2020 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 14,000,000 |  | Kč 1,101,000,000 |
Euro Member Countries, Euro | 2020 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 16,000,000 | 9,000,000 |  |
Euro Member Countries, Euro | 2021 [Member] | US Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.82532 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.29394 |  |  |  |
Euro Member Countries, Euro | 2021 [Member] | British Pound [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.92098 |  |  |  |
Euro Member Countries, Euro | 2021 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 7,000,000 |  |  |
Euro Member Countries, Euro | 2021 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 11,000,000 | £ 6,000,000 |  |
Euro Member Countries, Euro | 2022 [Member] | US Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.75974 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.31155 |  |  |  |
Euro Member Countries, Euro | 2022 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | 1,000,000 |  |  |
Euro Member Countries, Euro | 2022 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives |  | $ 1,000,000 |  |  |

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- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226000-175313 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4D -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=82924980&loc=SL51823488-111719 + Details
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