Classification and Fair Value Amounts of Derivative Instruments (Detail) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	$ 42	$ 56
Derivative liability, fair value	3	2
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	42	55
Derivative liability, fair value	1	1
Designated as Hedging Instrument | Interest rate contract | Other Long-Term Assets
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	33	46
Designated as Hedging Instrument | Foreign exchange contract | Accounts Payable And Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	1	1
Designated as Hedging Instrument | Foreign exchange contract | Prepaid expenses and other
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	9	9
Not Designated as Hedging Instrument | Foreign exchange contract | Accounts Payable And Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	$ 2	1
Not Designated as Hedging Instrument | Foreign exchange contract | Prepaid expenses and other
Derivatives, Fair Value [Line Items]
Derivative asset, fair value		$ 1