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Summary of Significant Accounting Policies - Additional Information (Details)
12 Months Ended
Dec. 31, 2019
USD ($)
Segment
Dec. 31, 2018
USD ($)
Accounting Policies [Abstract]    
Cash and cash equivalents, maturities three months or less  
Impairment charges of long-lived assets $ 0 $ 0
Reduction in research and development expenses $ 4,500,000 $ 5,000,000
Number of reportable segment | Segment 1