Supplemental Cash Flow Information - Summary of Supplemental Cash Flow Information (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012
Net cash provided by operating activities included:
Interest paid (net of amounts capitalized)	$ 166		$ 69
Net income taxes paid to taxing authorities	1,027	[1]	776	[1]
Non-cash investing and financing activities:
Capital lease obligations increase	61		43
Property, plant and equipment sold	43		0
Acquisitions:
Contingent consideration	600	[2]	0	[2]
Payable to seller	6	[2]	0	[2]
Intangible asset acquired	0		3
Liability assumed	0		2
Income taxes paid to Marathon Oil under tax sharing agreement			$ 181

[1] U.S. and most state income taxes, if incurred, were paid by Marathon Oil for periods prior to the June 30, 2011 spinoff transaction. The amount for 2012 includes payments of $181 million for 2011 return period income taxes made to Marathon Oil under our tax sharing agreement and in return we received an equal amount of tax credits. See Note 22.

[2] See Note 4.