Quarterly report pursuant to Section 13 or 15(d)

Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Detail)

v3.8.0.1
Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Detail) - shares
shares in Millions
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Earnings Per Share [Abstract]    
Weighted-average shares used in basic computations 72.7 83.1
Dilutive effect of exercise of equity grants outstanding 3.6 3.6
Weighted-average shares used in diluted computations 76.3 86.7