Financial Instruments, Hedging Activities and Fair Value Measurements (Assets and Liabilities Reported at Fair Value on a Recurring Basis) (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Level 1 | Short-term Investments | Marketable Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments reported at fair value on a recurring basis	$ 4	$ 4
Level 1 | Investments | Marketable Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments reported at fair value on a recurring basis	79	78
Level 2 | Other Current Assets | Foreign Currency Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets reported at fair value on a recurring basis	6	22
Level 2 | Other Current Assets | Cross Currency Swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets reported at fair value on a recurring basis	2	0
Level 2 | Other Assets | Cross Currency Swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets reported at fair value on a recurring basis		65
Level 2 | Accounts Payable and Accrued Liabilities | Foreign Currency Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities reported at fair value on a recurring basis	$ 23	$ 9