Charges and Credits - Summary of Charges (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended	9 Months Ended
	Jun. 30, 2013	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Jun. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Investment In Joint Venture [Line Items]
Charges, Pretax	$ (664)	$ 32			$ 68	$ (572)
Charges, Tax	19					19
Charges, Net	(683)	28	21	13		(591)	62
Charges, Net						456
Gain on formation of OneSubsea joint venture
Investment In Joint Venture [Line Items]
Charges, Pretax	(1,028)					(1,028)
Charges, Tax
Charges, Net	(1,028)
Charges, Net						(1,028)
Impairment of equity-method investments
Investment In Joint Venture [Line Items]
Charges, Pretax	364					364
Charges, Tax	19					19
Charges, Net	345
Charges, Net						345
Currency devaluation loss In Venezuela
Investment In Joint Venture [Line Items]
Charges, Pretax						92
Charges, Tax
Charges, Net						$ 92