Debt Obligations and Commitments - Additional Information (Detail) (USD $)		3 Months Ended			9 Months Ended				9 Months Ended		3 Months Ended
	Sep. 07, 2013	Sep. 07, 2013 Five Year Unsecured Revolving Credit Agreement	Sep. 07, 2013 Three Sixty Four Day Unsecured Revolving Credit Agreement	Sep. 07, 2013 Four Year Unsecured Revolving Credit Agreement	Sep. 07, 2013 Notes Due 2016 Floating Rate Notes Due 2016	Mar. 23, 2013 Notes Due 2016 Floating Rate Notes Due 2016	Mar. 23, 2013 Notes Due 2016 0.700% Senior Notes Due 2016	Mar. 23, 2013 Notes Due 2023 2.750% Senior Notes Due 2023	Sep. 07, 2013 Notes Due 2015 Floating Rate Notes Due 2015	Sep. 07, 2013 Notes Due 2019 2.250% Senior Notes Due 2019	Sep. 07, 2013 Notes Due 2014
Debt Instrument [Line Items]
Fixed and floating rate notes issued						$ 625,000,000	$ 625,000,000	$ 1,250,000,000	$ 850,000,000	$ 850,000,000
LIBOR term					3 months				3 months
Basis spread on LIBOR					0.21%				0.00%
Interest rate on debt							0.70%	2.75%		2.25%
Repayments of Senior Debt											1,000,000,000
Line of Credit Facility, Expiration Date		Jun. 10, 2018	Jun. 09, 2014
Debt Instrument, Term of Agreement		5 years	364 days
Line of Credit Facility, Maximum Borrowing Capacity		2,925,000,000	2,925,000,000
Line Of Credit Facility Increase Additional Borrowing Capacity		3,500,000,000	3,500,000,000
Line of Credit Facility Replaced			2,925,000,000	2,925,000,000
Commercial paper outstanding	$ 2,000,000,000