Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Basic EPS Calculation
Earnings available to common stockholders - Basic	$ 15,625	$ (5,543)	$ 2,924
Weighted-average number of common shares outstanding (in shares)	1,916	1,870	1,882
Add: Deferred awards held as stock units (in shares)	0	0	0
Total weighted-average number of common shares outstanding (in shares)	1,916	1,870	1,882
Earnings per share of common stock - Basic (in dollars per share)	$ 8.15	$ (2.96)	$ 1.55
Diluted EPS Calculation
Earnings available to common stockholders - Diluted	$ 15,625	$ (5,543)	$ 2,924
Weighted-average number of common shares outstanding (in shares)	1,916	1,870	1,882
Add: Deferred awards held as stock units (in shares)	0	0	0
Add: Dilutive effect of employee stock-based awards (in shares)	4	0	13
Total weighted-average number of common shares outstanding (in shares)	1,920	1,870	1,895
Earnings per share of common stock - Diluted (in dollars per share)	$ 8.14	$ (2.96)	$ 1.54
Antidilutive securities excluded from computation of earnings per share (in shares)	1