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Summary of Significant Accounting Policies - Schedule of fair value valuation (Details)
Dec. 31, 2018
$ / shares
Fair Value Measurement Inputs and Valuation Techniques [Line Items]  
Expected term (in years) 2 years
Fair value of underlying shares (in dollars per share)  
Fair Value Measurement Inputs and Valuation Techniques [Line Items]  
Measurement input 19.02
Volatility  
Fair Value Measurement Inputs and Valuation Techniques [Line Items]  
Measurement input 0.550
Risk-free interest rate  
Fair Value Measurement Inputs and Valuation Techniques [Line Items]  
Measurement input 0.0248
Dividend yield  
Fair Value Measurement Inputs and Valuation Techniques [Line Items]  
Measurement input 0