Consolidated Balance Sheets (Parentheticals) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Class A common stock [Member]
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	180,000,000	180,000,000
Common Stock, Shares, Issued	64,584,102	57,882,442
Common Stock, Shares, Outstanding	51,934,137	45,359,083
Treasury Stock, Shares	12,649,965	12,523,359
Class B common stock [Member]
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	30,000,000	30,000,000
Common Stock, Shares, Issued	1,608,989	1,728,952
Common Stock, Shares, Outstanding	1,608,989	1,728,952