Other Financial Information (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014		Dec. 31, 2013
Segment Reporting Information [Line Items]
Total financing interest and debt costs		$ 495	$ 358		$ 284
Less: Capitalized interest		495	358		284
Interest and debt expense		0	0		0
Research and development expenses		601	707		750
Excess of replacement cost over the carrying value of inventories (LIFO method)		3,745	8,135		9,150
LIFO (losses) / profits on inventory drawdowns included in earnings		(65)	13		14
Foreign currency effects	[1]	769	487		474
Gains on sale of nonstrategic properties		2,300	3,000
Gain (loss) for impairments and other assets write-offs		3,000	1,000
Company share of equity affiliates foreign currency effects		344	118		$ 244
Goodwill		4,588	4,593	[2]
Other Assets and Investments [Member]
Segment Reporting Information [Line Items]
Gain (loss) for impairments and other assets write-offs			200
Downstream [Member]
Segment Reporting Information [Line Items]
Gains on sale of nonstrategic properties		1,800	1,000
Upstream [Member]
Segment Reporting Information [Line Items]
Gains on sale of nonstrategic properties		$ 500	1,800
Gain (loss) for impairments and other assets write-offs			$ 800

[1] Includes $344, $118 and $244 in 2015, 2014 and 2013, respectively, for the company’s share of equity affiliates’ foreign currency effects.

[2] 2014 conformed to 2015 presentation