CONSOLIDATED BALANCE SHEETS (Parentheticals) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2013
Dec. 31, 2012
Accounts receivable, allowance for doubtful accounts (in dollars) $ 674 $ 367
Preferred stock, no par value (in dollars per share)      
Preferred stock, shares authorized 3,000 3,000
Preferred stock, shares issued      
Treasury stock, a cost, shares 1,241 1,562
Class A common stock
   
Common stock, no par value (in dollars per share)      
Common stock, shares authorized 30,000 30,000
Common stock, shares issued 20,069 17,171
Common stock, shares outstanding 18,828 15,609
Class B common stock
   
Common stock, no par value (in dollars per share)      
Common stock, shares authorized 5,000 5,000
Common stock, shares issued