Annual report pursuant to Section 13 and 15(d)

Cash Equivalents And Investments (Schedule Of Estimated Fair Value Of Available-For-Sale Securities) (Details)

v3.7.0.1
Cash Equivalents And Investments (Schedule Of Estimated Fair Value Of Available-For-Sale Securities) (Details) - USD ($)
Dec. 31, 2016
Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]    
Fair Value $ 9,656,000 $ 13,466,000
Investments [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost, Due within one year 5,802,000  
Amortized Cost, Due after one year through five years 0  
Amortized Cost 5,802,000  
Fair Value, Due within one year 5,805,000  
Fair Value, Due after one year through five years 0  
Fair Value $ 5,805,000 $ 11,522,000