Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	Jun. 28, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair values of debt instruments	$ 9,600	$ 7,900
Outstanding principal amount of debt instruments	9,300	7,000
Unamortized discount on long-term debt	884	872
Foreign currency contracts | Designated as hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate notional amount of derivatives	1,300	804
Interest rate swaps | Designated as hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate notional amount of derivatives	$ 1,300	$ 1,300