Quarterly report pursuant to Section 13 or 15(d)

Cash Equivalents and Investments (Schedule of Cash Equivalents and Available-for-Sale Securities) (Details)

v3.19.3
Cash Equivalents and Investments (Schedule of Cash Equivalents and Available-for-Sale Securities) (Details) - USD ($)
Sep. 30, 2019
Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost $ 16,219,000 $ 8,428,000
Gross Unrealized Gains
Gross Unrealized Losses 0
Fair Value 16,219,000 8,428,000
Cash Equivalents 10,716,000 8,428,000
Short-Term Investments 5,502,752
Long-Term Investments
Cash Equivalents [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 10,716,000  
Gross Unrealized Gains  
Fair Value 10,716,000  
Cash Equivalents 10,716,000  
Short-Term Investments  
Long-Term Investments  
Cash Equivalents [Member] | Money Market Funds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 10,716,000 8,428,000
Gross Unrealized Gains
Gross Unrealized Losses  
Fair Value 10,716,000 8,428,000
Cash Equivalents 10,716,000 8,428,000
Short-Term Investments
Long-Term Investments
Investments [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 5,503,000  
Gross Unrealized Gains  
Fair Value 5,503,000  
Short-Term Investments 5,503,000  
Long-Term Investments  
Investments [Member] | Commercial Paper [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 4,491,000  
Gross Unrealized Gains  
Fair Value 4,491,000  
Short-Term Investments 4,491,000  
Long-Term Investments  
Investments [Member] | Corporate Notes/Bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 1,012,000  
Gross Unrealized Gains  
Fair Value 1,012,000  
Short-Term Investments 1,012,000  
Long-Term Investments