v2.4.0.6
Capital Stock (Details) (USD $)
1 Months Ended
Nov. 30, 2011
Dec. 31, 2011
Nov. 15, 2011
Dec. 31, 2010
Mar. 31, 2010
Accumulated Other Comprehensive Income          
Foreign currency translation   21,066,000   23,010,000  
Unrealized gain on marketable debt securities   2,103,000   4,794,000  
Other   (1,107,000)   (936,000)  
Total accumulated other comprehensive income   22,062,000   26,868,000  
3 7/8 % Convertible Senior Notes due 2011 upon maturity
         
Capital Stock          
Interest rate (as a percent) 3.875% 3.875% 3.875% 3.875% 3.875%
Aggregate shares of common stock issued for the conversion value in excess of the principal amount 943,714        
Principal amount repaid $ 230,000,000