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Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Summary Of Significant Accounting Policies [Line Items]    
Restricted cash (non-current) related to letter of credit $ 245,000 $ 84,000
Fair value assets transferred from level 1 to level 2 0 0
Fair value assets transferred from level 2 to level 1 0 0
Fair value liabilities transferred from level 1 to level 2 0 0
Fair value liabilities transferred from level 2 to level 1 0 0
Fair value measurement with unobservable inputs reconciliation recurring basis asset transfers net 0 0
Fair value measurement with unobservable inputs reconciliation recurring basis liabilities transfers net 0 0
Asset impairment charges on long-lived assets 0  
Dividend yield 0  
Uncertain tax positions 0  
Interest charges or penalties related to unrecognized tax benefits 0  
Cash, cash equivalents and restricted cash at beginning of period 7,126,000 53,349,000
Cash, cash equivalents and restricted cash at end of period 34,019,000 7,126,000
ASU 2016-18    
Summary Of Significant Accounting Policies [Line Items]    
Cash, cash equivalents and restricted cash at beginning of period $ 84,000,000 0
Cash, cash equivalents and restricted cash at end of period   $ 84,000,000