Financial Instruments, Hedging Activities and Fair Value Measurements (Assets and Liabilities Reported at Fair Value on a Recurring Basis) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
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	$ 5	$ 5
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	74	70
Level 2 | Short-term Investments | Commercial Paper And Restricted Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments reported at fair value on a recurring basis		50
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	52	25
Level 2 | Other Current Assets | Equity Forward Arrangement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets reported at fair value on a recurring basis	268	207
Level 2 | Other 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	16	2
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	7
Level 2 | Other 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		11
Level 2 | Other Liabilities | Cross Currency Swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities reported at fair value on a recurring basis	$ 32	$ 120