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Cash, Cash Equivalents and Short-Term Investments - Summary of Short-term Investments with Unrealized Losses (Details)
Dec. 31, 2018
USD ($)
Cash And Cash Equivalents And Short Term Investments [Line Items]  
Less Than 12 Months, Estimated Fair Value $ 10,976,777
Less Than 12 Months, Unrealized Losses. (9,796)
US Treasury Securities  
Cash And Cash Equivalents And Short Term Investments [Line Items]  
Less Than 12 Months, Estimated Fair Value 1,987,630
Less Than 12 Months, Unrealized Losses. (164)
Corporate Debt Securities  
Cash And Cash Equivalents And Short Term Investments [Line Items]  
Less Than 12 Months, Estimated Fair Value 5,957,235
Less Than 12 Months, Unrealized Losses. (6,678)
Asset-backed Securities  
Cash And Cash Equivalents And Short Term Investments [Line Items]  
Less Than 12 Months, Estimated Fair Value 3,031,912
Less Than 12 Months, Unrealized Losses. $ (2,954)