Stockholders' Equity - Additional Information (Detail) | May 20, 2020USD ($)$ / sharesshares | Jan. 07, 2020USD ($)$ / sharesshares | Oct. 18, 2019USD ($) | Jun. 30, 2020USD ($)$ / sharesshares | Apr. 30, 2019USD ($)$ / sharesshares | Jun. 30, 2020USD ($)$ / sharesshares | Jun. 30, 2019USD ($)shares | Mar. 31, 2020shares |
Stockholders Equity [Line Items] | | | | | | | | |
Proceeds from issuance of common stock and warrants | | | | | | $ 1,171,586 | $ 11,168,773 | |
Change in fair value of warrant liability | | | | | | 3,263,271 | $ (2,938,242) | |
Gain on warrant exchange | | | | | | $ 2,228,697 | | |
Common Stock [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Exercise price | $ / shares | | | | $ 1.80 | | $ 1.80 | | |
Sale Agreement [Member] | Jefferies [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Payment of commission rate from gross proceeds | | | 3.00% | | | | | |
Number of shares issued upon new issue | shares | | | | | | 891,944 | | |
Available for offering | | | | $ 27,000,000 | | $ 27,000,000 | | |
Proceeds from issuance of common stock | | | | | | 1,300,000 | | |
Related cost offset the proceeds | | | | | | $ 100,000 | | |
Sale Agreement [Member] | Jefferies [Member] | Maximum [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Aggregate offering | | | $ 30,000,000 | | | | | |
Securities Purchase Agreement [Member] | Eagle Pharmaceuticals, Inc [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Common stock price per share | $ / shares | | $ 2 | | | | | | |
Milestone payments upon occurrence of milestone event payable | | $ 20,000,000 | | | | | | |
Milestone payments upon occurrence of milestone event payable in cash | | 10,000,000 | | | | | | |
Milestone payments upon occurrence of milestone event payable in shares | | $ 10,000,000 | | | | | | |
Milestone payments upon occurrence of milestone event payable in shares, Percentage of premium over share price | | 15.00% | | | | | | |
Restricted period for Sale of shares description | | shares will be restricted from sale until the earlier of three months following the milestone event or the three-year anniversary of the agreement | | | | | | |
Securities Purchase Agreement [Member] | Eagle Pharmaceuticals, Inc [Member] | Common Stock [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Number of shares issued upon new issue | shares | | 10,000,000 | | | | | | |
Proceeds from issuance of common stock | | $ 20,000,000 | | | | | | |
Common stock price per share | $ / shares | | $ 2 | | | | | | |
Underwriters Public Offering [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Common stock purchase warrants | shares | | | | | 8,000,000 | | | |
Proceeds from issuance of common stock and warrants | | | | | $ 11,300,000 | | | |
Exercise price | $ / shares | | | | | $ 2 | | | |
Warrants issued for common stock dividends | | | | | 1 | | | |
Underwriters Public Offering [Member] | Common Stock [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Number of shares issued upon new issue | shares | | | | | | | 8,000,000 | |
Common stock price per share | $ / shares | | | | | $ 1.50 | | | |
Underwriters Public Offering [Member] | Maximum [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Number of shares that can be purchased with warrants | shares | | | | | 8,000,000 | | | |
Share Exchange Agreements [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Number of shares that can be purchased with warrants | shares | 5,833,333 | | | | | | | |
Share leak-out agreement trading restrictions on exchange shares description | | | | | | trading restrictions with respect to the Exchange Shares, which (i) for the first 90 days, prohibit any sales of Exchange Shares, (ii) for the subsequent 90 days, limit sales of Exchange Shares on any day to 2.5% of that day’s trading volume of Common Stock, and (iii) prohibit new short positions or short sales on Common Stock for the combined 180 day period. | | |
Fair value of warrants | $ 3,400,000 | | | | | | | |
Gain on warrant exchange | | | | | | $ 1,900,000 | | |
Share Exchange Agreements [Member] | Common Stock [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Number of shares issued upon new issue | shares | 2,406,250 | | | | | | | |
Warrant Exchange Agreements [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Number of shares that can be purchased with warrants | shares | 2,166,667 | | | | | | | |
Exercise price | $ / shares | $ 1.80 | | | | | | | |
Warrants expiration date | Apr. 2, 2024 | | | | | | | |
Number of common stock shares applicable for leak-out restrictions under leak-out agreement | shares | 893,750 | | | | | | | |
Fair value of warrants | $ 7,300,000 | | | | | | | |
Warrant Exchange Agreements [Member] | Other Income (Expense) [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Change in fair value of warrant liability | 3,700,000 | | | $ (400,000) | | $ (2,900,000) | | |
Gain on warrant exchange | 300,000 | | | | | | | |
Warrant Exchange Agreements [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Fair value of warrants | $ 1,700,000 | | | | | | | |
Warrant [Member] | Securities Purchase Agreement [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Common stock purchase warrants outstanding and exercisable | shares | | | | 3,074,551 | | 3,074,551 | | 8,907,884 |
Warrant [Member] | Warrant Exchange Agreements [Member] | Stock Price [Member] | Class Of Warrant Or Right Issued on April 2019 [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Fair value assumptions | 0.0170 | | | | | | | |
Warrant [Member] | Warrant Exchange Agreements [Member] | Stock Price [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Fair value assumptions | 0.0164 | | | | | | | |
Warrant [Member] | Warrant Exchange Agreements [Member] | Volatility [Member] | Class Of Warrant Or Right Issued on April 2019 [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Fair value assumptions | 0.73 | | | | | | | |
Warrant [Member] | Warrant Exchange Agreements [Member] | Volatility [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Fair value assumptions | 0.73 | | | | | | | |
Warrant [Member] | Warrant Exchange Agreements [Member] | Remaining Term [Member] | Class Of Warrant Or Right Issued on April 2019 [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Fair value assumptions | 3 years 10 months 13 days | | | | | | | |
Warrant [Member] | Warrant Exchange Agreements [Member] | Remaining Term [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Fair value assumptions | 3 years 10 months 13 days | | | | | | | |
Warrant [Member] | Warrant Exchange Agreements [Member] | Risk-free Interest Rate [Member] | Class Of Warrant Or Right Issued on April 2019 [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Fair value assumptions | 0.0028 | | | | | | | |
Warrant [Member] | Warrant Exchange Agreements [Member] | Risk-free Interest Rate [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Fair value assumptions | 0.0027 | | | | | | | |
Warrant [Member] | Warrant Exchange Agreements [Member] | Discount for Lack of Marketability [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | | | | | | | | |
Stockholders Equity [Line Items] | | | | | | | | |
Fair value assumptions | 0.07 | | | | | | | |