Summary of Significant Accounting Policies - Schedule of assumptions used for valuation (Details)	Mar. 30, 2019 $ / shares	Mar. 31, 2018 $ / shares
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Expected term (in years)	2 years	3 years
Fair value of underlying shares (in dollars per share)	$ 19.49	$ 3.00
Volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input (as a percent)	0.55	0.55
Risk-free interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input (as a percent)	0.0227	0.0198
Dividend yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input (as a percent)	0	0