Equity and Share-Based Compensation (Weighted Average Common Shares Outstanding) (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Equity [Abstract]
Weighted average number of common shares outstanding – basic (in shares)	4,588	4,577	4,593	4,571
Effect of dilutive securities (in shares)	77	51	75	45
Weighted-average number of common shares outstanding – diluted (in shares)	4,665	4,628	4,668	4,616