Consolidated Balance Sheets (Parenthetical) - shares
shares in Thousands
Dec. 31, 2016
Dec. 31, 2015
Preferred Stock, Shares Authorized 300 300
Preferred Stock, Shares Outstanding 0 0
Treasury Stock, Shares 3,616 3,194
Common Stock    
Common Stock, Shares Authorized 100,000 100,000
Common Stock, Shares, Issued 35,318 35,024
Class B Common Shares    
Common Stock, Shares Authorized 12,000 12,000
Common Stock, Shares, Issued 729 734