Quarterly report pursuant to Section 13 or 15(d)

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical)

v3.8.0.1
CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - $ / shares
Sep. 30, 2017
Dec. 31, 2016
Convertible preferred stock issued 0 0
Common Class A [Member]    
Common stock, par value $ 0.01 $ 0.01
Common stock, shares authorized 100,000,000 100,000,000
Common stock, shares issued 63,456,698 62,967,061
Common stock, shares outstanding 31,166,205 32,703,865
Treasury stock, shares 32,290,493 30,263,196
Common Class B [Member]    
Common stock, par value $ 0.01 $ 0.01
Common stock, shares authorized 30,000,000 30,000,000
Common stock, shares issued 12,029,375 12,029,375
Common stock, shares outstanding 12,029,375 12,029,375