Description of Business and Summary of Significant Accounting Policies - Schedule of Computation of Diluted Net Loss per Share of Common Stock Attributable to Common Stockholders (Parenthetical) (Details) - USD ($)	Jun. 30, 2021	Jun. 30, 2020	Aug. 31, 2018	Dec. 31, 2014
Secured Convertible Promissory Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Secured convertible promissory notes	$ 4,000,000.0	$ 4,000,000.0	$ 4,000,000.0	$ 4,000,000.0
Four Convertible Promissory Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Aggregate principal amount	$ 9,500,000	$ 9,500,000