XML 49 R37.htm IDEA: XBRL DOCUMENT v3.19.1
Fair Value of Financial Instruments - Schedule of Cost, Fair Value and Maturities of Short Term Investments (Details) - USD ($)
Mar. 31, 2019
Dec. 31, 2018
Short-term investments - Cost $ 20,079,944 $ 14,257,998
Short-term investments - Fair Value 20,166,768 14,257,998
Short-term investment maturities - Within 3 months, cost 6,452,955 5,383,488
Short-term investment maturities - Between 3-12 months, cost 13,626,989 8,844,638
Total, cost 20,079,944 14,228,126
Short-term investment maturities - Within 3 months, fair value 6,489,330 5,393,743
Short-term investment maturities - Between 3-12 months, fair value 13,677,438 8,864,255
Total, fair value 20,166,768 14,257,998
Corporate Debt Securities [Member]    
Short-term investments - Cost 20,079,944 14,228,126
Short-term investments - Fair Value $ 20,166,768 $ 14,228,126