Annual report pursuant to Section 13 and 15(d)

Basis of Presentation - Common Share Amounts Used to Compute Basic and Diluted Earnings per Share (Detail)

v3.3.1.900
Basis of Presentation - Common Share Amounts Used to Compute Basic and Diluted Earnings per Share (Detail) - shares
shares in Millions
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Earnings Per Share [Abstract]      
Weighted average shares used in basic computations 82.6 86.3 102.6
Dilutive effect of exercise of equity grants outstanding 2.7 4.5 4.8
Weighted average shares used in diluted computations 85.3 90.8 107.4