Stockholders' Equity - Additional Information (Detail)				1 Months Ended	3 Months Ended			7 Months Ended	9 Months Ended
	May 20, 2020 USD ($) $ / shares shares	Jan. 07, 2020 USD ($) $ / shares shares	Oct. 18, 2019 USD ($)	Apr. 30, 2019 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) shares	Jun. 30, 2019 shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($)	Mar. 31, 2020 shares
Stockholders Equity [Line Items]
Proceeds from issuance of common stock and warrants									$ 5,806,133	$ 11,621,325
Change in fair value of warrant liability					$ 228,750	$ 425,795			3,002,449	(2,593,601)
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	$ 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									4,453,939
Available for offering					$ 22,200,000			$ 22,200,000	$ 22,200,000
Proceeds from issuance of common stock									6,100,000
Related cost offset the proceeds									$ 300,000
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		$ 2.00
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		$ 2.00
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				$ 2.00
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						582,968	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. 02, 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							$ (700,000)		$ (2,600,000)
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	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