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Debt and Commitments - Schedule of Company's Long-Term Debt (Parenthetical) (Detail) € in Millions, CAD in Millions, $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2015 USD ($) | Dec. 31, 2015 CAD | Dec. 31, 2015 EUR (€) | Dec. 31, 2014
3.625% Fixed-Rate Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Senior Notes, face amount | $ 750 |  |  |
Senior Notes, due year | 2024 |  |  |
Interest rate | 3.625% | 3.625% | 3.625% |
4.150% Fixed-Rate Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Senior Notes, face amount | $ 650 |  |  |
Senior Notes, due year | 2025 |  |  |
Interest rate | 4.15% | 4.15% | 4.15% |
1.900% Fixed-Rate Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Senior Notes, face amount | € |  |  | € 550 |
Senior Notes, due year | 2023 |  |  |
Interest rate | 1.90% | 1.90% | 1.90% |
3.100% Fixed-Rate Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Senior Notes, face amount | CAD |  | CAD 425 |  |
Senior Notes, due year | 2022 |  |  |
Interest rate | 3.10% | 3.10% | 3.10% |
Bank Term Debt [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Weighted average interest rate of bank term debt | 8.10% | 8.10% | 8.10% | 8.20%
Government Loans [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Weighted average interest rate of bank term debt | 3.70% | 3.70% | 3.70% | 5.50%

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