Common Stock (Details) - USD ($)	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Nov. 30, 2019
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased (in shares)		3,100,000
Payments for repurchase of common stock	$ 0	$ 300,000,000
Stock-based compensation, shares issued during period (in shares)	3,400,000	4,200,000
Common Stock
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased (in shares)	0
Share repurchases program, authorized amount (up to)			$ 2,500,000,000
Stock repurchase program, remaining authorized repurchase amount	$ 2,400,000,000