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Financial Instruments - Foreign Exchange Forward Contracts Representing Commitments to Buy and Sell Various Foreign Currencies (Detail) - 12 months ended Dec. 31, 2015 | USD ($) | GBP (£) | MXN | CZK | EUR (€)
--- | --- | --- | --- | --- | ---
Euros [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (142,000,000) | £ (22,000,000) |  | CZK 6,574,000,000 |
Euros [Member] | 2016 [Member] | U S Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.87463 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.20933 |  |  |  |
Euros [Member] | 2016 [Member] | British Pound [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.40949 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.80758 |  |  |  |
Euros [Member] | 2016 [Member] | Czech Koruna [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.03709 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 26.84500 |  |  |  |
Euros [Member] | 2016 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ 101,000,000 | 11,000,000 |  | 3,377,000,000 |
Euros [Member] | 2016 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (153,000,000) | (13,000,000) |  | (2,000,000) |
Euros [Member] | 2017 [Member] | U S Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.88127 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.23216 |  |  |  |
Euros [Member] | 2017 [Member] | British Pound [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.81324 |  |  |  |
Euros [Member] | 2017 [Member] | Czech Koruna [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.03720 |  |  |  |
Euros [Member] | 2017 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ 38,000,000 |  |  | 2,168,000,000 |
Euros [Member] | 2017 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (84,000,000) | (9,000,000) |  |  |
Euros [Member] | 2018 [Member] | U S Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.87239 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.18114 |  |  |  |
Euros [Member] | 2018 [Member] | British Pound [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.73974 |  |  |  |
Euros [Member] | 2018 [Member] | Czech Koruna [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.03774 |  |  |  |
Euros [Member] | 2018 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ 15,000,000 |  |  | CZK 1,031,000,000 |
Euros [Member] | 2018 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (45,000,000) | (7,000,000) |  |  |
Euros [Member] | 2019 [Member] | U S Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.85873 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.16813 |  |  |  |
Euros [Member] | 2019 [Member] | British Pound [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.74603 |  |  |  |
Euros [Member] | 2019 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ 5,000,000 |  |  |  |
Euros [Member] | 2019 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (17,000,000) | £ (4,000,000) |  |  |
Euros [Member] | 2020 [Member] | U S Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 1.17400 |  |  |  |
Euros [Member] | 2020 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (2,000,000) |  |  |  |
Canadian Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (2,037,000,000) |  |  |  | € 47,000,000
Canadian Dollar [Member] | 2016 [Member] | U S Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.30051 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.82317 |  |  |  |
Canadian Dollar [Member] | 2016 [Member] | Euro [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.45543 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.67901 |  |  |  |
Canadian Dollar [Member] | 2016 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ 276,000,000 |  |  |  | 44,000,000
Canadian Dollar [Member] | 2016 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (932,000,000) |  |  |  | (11,000,000)
Canadian Dollar [Member] | 2017 [Member] | U S Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.23553 |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.81685 |  |  |  |
Canadian Dollar [Member] | 2017 [Member] | Euro [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 1.44220 |  |  |  |
Canadian Dollar [Member] | 2017 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ 7,000,000 |  |  |  | € 14,000,000
Canadian Dollar [Member] | 2017 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (577,000,000) |  |  |  |
Canadian Dollar [Member] | 2018 [Member] | U S Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.79299 |  |  |  |
Canadian Dollar [Member] | 2018 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (416,000,000) |  |  |  |
Canadian Dollar [Member] | 2019 [Member] | U S Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.78519 |  |  |  |
Canadian Dollar [Member] | 2019 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (278,000,000) |  |  |  |
Canadian Dollar [Member] | 2020 [Member] | U S Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Sales Exchange Rate | 0.76577 |  |  |  |
Canadian Dollar [Member] | 2020 [Member] | Short [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | $ (117,000,000) |  |  |  |
U S Dollar [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | MXN |  |  | MXN 7,717,000,000 |  |
U S Dollar [Member] | 2016 [Member] | Mexican Peso [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.06751 |  |  |  |
U S Dollar [Member] | 2016 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | MXN |  |  | 4,248,000,000 |  |
U S Dollar [Member] | 2017 [Member] | Mexican Peso [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.06269 |  |  |  |
U S Dollar [Member] | 2017 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | MXN |  |  | 2,689,000,000 |  |
U S Dollar [Member] | 2018 [Member] | Mexican Peso [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Foreign exchange forward contract, Purchases Exchange Rate | 0.05619 |  |  |  |
U S Dollar [Member] | 2018 [Member] | Long [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional amount of foreign currency derivatives | MXN |  |  | MXN 780,000,000 |  |

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