Earnings Per Share - Schedule of Computations of Weighted Average Shares Outstanding (Detail) - shares shares in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share [Abstract]
Basic (in shares)	425.4	424.2	425.1	424.0
Dilutive securities (in shares)	2.4	0.5	2.6	0.0
Diluted weighted average shares outstanding (in shares)	427.8	424.7	427.7	424.0