Annual report pursuant to Section 13 and 15(d)

CONSOLIDATED BALANCE SHEETS (Parenthetical)

v3.6.0.2
CONSOLIDATED BALANCE SHEETS (Parenthetical) - shares
shares in Millions
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Treasury stock, shares 1 1    
Common Stock | Class A Common Stock:        
Common stock, shares issued 180 194 201 212
Common Stock | Class B Common Stock:        
Common stock, shares issued 689 693 705 712