Information Relating to the Consolidated Statement of Cash Flows - Summary of Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Distributions less than income from equity affiliates includes the following:
Distributions from equity affiliates	$ 728	$ 971
(Income) loss from equity affiliates	1,550	(2,258)
Distributions less than income from equity affiliates	2,278	(1,287)
Net decrease (increase) in operating working capital was composed of the following:
Decrease (increase) in accounts and notes receivable	4,769	910
Decrease (increase) in inventories	371	(878)
Decrease (increase) in prepaid expenses and other current assets	392	(303)
Increase (decrease) in accounts payable and accrued liabilities	(4,812)	284
Increase (decrease) in income and other taxes payable	(1,093)	(292)
Net decrease (increase) in operating working capital	(373)	(279)
Net cash provided by operating activities includes the following cash payments:
Interest on debt (net of capitalized interest)	328	443
Income taxes	2,142	2,590
Proceeds and deposits related to asset sales and returns of investment consisted of the following gross amounts:
Proceeds and deposits related to asset sales	1,821	891
Returns of investment from equity affiliates	31	46
Proceeds and deposits related to asset sales and returns of investment	1,852	937
Net maturities (investments) of time deposits consisted of the following gross amounts:
Investments in time deposits	0	0
Maturities of time deposits	0	950
Net maturities of (investments in) time deposits	0	950
Net sales (purchases) of marketable securities consisted of the following gross amounts:
Marketable securities purchased	(1)	(1)
Marketable securities sold	0	3
Net sales (purchases) of marketable securities	(1)	2
Net repayment (borrowing) of loans by equity affiliates:
Borrowing of loans by equity affiliates	(1,100)	(675)
Repayment of loans by equity affiliates	26	55
Net repayment (borrowing) of loans by equity affiliates	(1,074)	(620)
Net borrowings (repayments) of short-term obligations consisted of the following gross and net amounts:
Proceeds from issuances of short-term obligations	7,922	614
Repayments of short-term obligations	(2,150)	(366)
Net borrowings (repayments) of short-term obligations with three months or less maturity	(3,201)	(437)
Net borrowings (repayments) of short-term obligations	2,571	(189)
Net sales (purchases) of treasury shares consists of the following gross and net amounts:
Shares issued for share-based compensation plans	201	699
Shares purchased under share repurchase and deferred compensation plans	(1,751)	(1,539)
Net sales (purchases) of treasury shares	(1,550)	(840)
Capital expenditures
Additions to properties, plant and equipment	4,991	6,381
Additions to investments	44	40
Current-year dry hole expenditures	223	103
Payments for other assets and liabilities, net	(33)	13
Capital expenditures	5,225	6,537
Expensed exploration expenditures	208	207
Assets acquired through finance lease obligations and other financing obligations	6	147
Payments for other assets and liabilities, net	33	(13)
Capital and exploratory expenditures, excluding equity affiliates	5,472	6,878
Company's share of expenditures by equity affiliates	2,258	3,144
Capital and exploratory expenditures, including equity affiliates	$ 7,730	$ 10,022