Debt - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2014
Debt Instrument [Line Items]
Unsecured fixed-rate notes issued	$ 600
Unsecured fixed-rate notes issued, net of discount	598
Repayments of debt	500
Retirement of various lease obligations	152
Coupon Rate of 1.3% Notes Mature in June 2017 [Member]
Debt Instrument [Line Items]
Unsecured fixed-rate notes issued	300
Coupon rate	1.30%
Debt notes maturity period	Jun. 30, 2017
Coupon Rate of 3.5% Notes Mature in July 2024 [Member]
Debt Instrument [Line Items]
Unsecured fixed-rate notes issued	300
Coupon rate	3.50%
Debt notes maturity period	Jul. 31, 2024
Unsecured Fixed-Rate Notes [Member]
Debt Instrument [Line Items]
Repayments of debt	250
WilcoHess [Member]
Debt Instrument [Line Items]
Repayments of debt	$ 74