Quarterly report pursuant to Section 13 or 15(d)

Per Share Data and Stockholders' Equity - Additional Information (Detail)

v3.5.0.2
Per Share Data and Stockholders' Equity - Additional Information (Detail) - shares
shares in Millions
9 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Common Class A [Member]    
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]    
Antidilutive stock options excluded in computation of diluted earnings per share 0.2 0.5