Changes in Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ 49,218	$ 43,155	$ 45,406	$ 29,849
Net Income	5,145	2,091	10,904	3,073
Other comprehensive income (loss)	(505)	160	(363)	298
Dividends declared, ordinary	(598)	(583)	(1,201)	(1,171)
Dividends declared, variable return of cash	(896)		(1,286)
Repurchase of company common stock	(2,300)	(606)	(3,725)	(981)
Distributed under benefit plans	138	59	464	82
Acquisition of Concho				13,125
Other	0		3	1
Ending Balance	$ 50,202	$ 44,276	$ 50,202	$ 44,276
Dividends declared, ordinary (in dollars per share)	$ 0.46	$ 0.43	$ 0.92	$ 0.86
Dividends declared, variable return of cash (in dollars per share)	$ 0.70		$ 1.00
Par Value
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ 21	$ 21	$ 21	$ 18
Acquisition of Concho				3
Ending Balance	21	21	21	21
Capital in Excess of Par
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	60,907	60,278	60,581	47,133
Distributed under benefit plans	138	59	464	82
Acquisition of Concho				13,122
Ending Balance	61,045	60,337	61,045	60,337
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(52,344)	(47,672)	(50,920)	(47,297)
Repurchase of company common stock	(2,300)	(606)	(3,725)	(981)
Other			1
Ending Balance	(54,644)	(48,278)	(54,644)	(48,278)
Accum. Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(4,808)	(5,080)	(4,950)	(5,218)
Other comprehensive income (loss)	(505)	160	(363)	298
Ending Balance	(5,313)	(4,920)	(5,313)	(4,920)
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	45,442	35,608	40,674	35,213
Net Income	5,145	2,091	10,904	3,073
Dividends declared, ordinary	(598)	(583)	(1,201)	(1,171)
Dividends declared, variable return of cash	(896)		(1,286)
Other			2	1
Ending Balance	$ 49,093	$ 37,116	$ 49,093	$ 37,116