Properties, Plant and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Properties, Plant and Equipment
Gross Investment at Cost	$ 336,077	$ 340,277	$ 327,289
Net Investment	182,186	188,396	183,173
Additions at Cost	17,623	28,002	36,332
Depreciation Expense	19,457	21,037	16,793
United States [Member]
Properties, Plant and Equipment
Gross Investment at Cost	111,987	122,550	125,163
Net Investment	52,541	56,791	59,960
Additions at Cost	5,158	7,639	10,857
Depreciation Expense	7,860	9,862	6,693
International [Member]
Properties, Plant and Equipment
Gross Investment at Cost	224,090	217,727	202,126
Net Investment	129,645	131,605	123,213
Additions at Cost	12,465	20,363	25,475
Depreciation Expense	11,597	11,175	10,100
Upstream [Member]
Properties, Plant and Equipment
Gross Investment at Cost	298,486	302,243	289,487
Net Investment	165,212	170,584	164,790
Additions at Cost	16,516	26,579	34,608
Depreciation Expense	17,823	19,348	14,815
Upstream [Member] | United States [Member]
Properties, Plant and Equipment
Gross Investment at Cost	83,929	93,848	96,850
Net Investment	39,710	43,125	45,864
Additions at Cost	4,432	6,586	9,688
Depreciation Expense	6,576	8,545	5,127
Upstream [Member] | International [Member]
Properties, Plant and Equipment
Gross Investment at Cost	214,557	208,395	192,637
Net Investment	125,502	127,459	118,926
Additions at Cost	12,084	19,993	24,920
Depreciation Expense	11,247	10,803	9,688
Downstream [Member]
Properties, Plant and Equipment
Gross Investment at Cost	32,145	32,379	31,974
Net Investment	14,290	14,897	15,238
Additions at Cost	903	1,061	1,118
Depreciation Expense	1,288	1,233	1,282
Downstream [Member] | United States [Member]
Properties, Plant and Equipment
Gross Investment at Cost	22,795	23,202	22,640
Net Investment	10,196	10,807	11,019
Additions at Cost	528	696	588
Depreciation Expense	956	878	886
Downstream [Member] | International [Member]
Properties, Plant and Equipment
Gross Investment at Cost	9,350	9,177	9,334
Net Investment	4,094	4,090	4,219
Additions at Cost	375	365	530
Depreciation Expense	332	355	396
All Other Segments [Member]
Properties, Plant and Equipment
Gross Investment at Cost	5,446	5,655	5,828
Net Investment	2,684	2,915	3,145
Additions at Cost	204	362	606
Depreciation Expense	346	456	696
All Other Segments [Member] | United States [Member]
Properties, Plant and Equipment
Gross Investment at Cost	5,263	5,500	5,673
Net Investment	2,635	2,859	3,077
Additions at Cost	198	357	581
Depreciation Expense	328	439	680
All Other Segments [Member] | International [Member]
Properties, Plant and Equipment
Gross Investment at Cost	183	155	155
Net Investment	49	56	68
Additions at Cost	6	5	25
Depreciation Expense	$ 18	$ 17	$ 16