Common Stock (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Nov. 30, 2019
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased (in shares)		0
Payments for repurchase of equity	$ 119,000,000
Payments for repurchase of common stock	$ 112,000,000	$ 0
Stock-based compensation, shares issued during period (in shares)	2,000,000.0	2,300,000
Common Stock
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased (in shares)	1,000,000.0
Share repurchases program, authorized amount (up to)			$ 2,500,000,000
Stock repurchase program, remaining authorized repurchase amount	$ 2,300,000,000