Quarterly report pursuant to Section 13 or 15(d)

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical)

v2.4.0.8
Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $)
Jun. 30, 2013
Dec. 31, 2012
Convertible preferred stock issued 0 0
Common Class A
   
Common stock, par value $ 0.01 $ 0.01
Common stock, shares authorized 100,000,000 100,000,000
Common stock, shares issued 61,535,416 61,352,134
Common stock, shares outstanding 40,767,025 41,210,507
Treasury stock, shares 20,768,391 20,141,627
Common Class B
   
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