Stockholders' Equity - Additional Information (Detail)					1 Months Ended	10 Months Ended	12 Months Ended
	Feb. 08, 2021 USD ($) $ / shares shares	May 20, 2020 USD ($) $ / shares shares	Jan. 07, 2020 USD ($) TradingDay $ / shares shares	Oct. 18, 2019 USD ($)	Apr. 30, 2019 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) $ / shares shares	Mar. 31, 2020 USD ($) $ / shares shares
Stockholders Equity [Line Items]
Preferred stock, authorized | shares						10,000,000	10,000,000	10,000,000
Preferred stock, par value | $ / shares						$ 0.0001	$ 0.0001	$ 0.0001
Preferred stock, issued | shares						0	0	0
Preferred stock, outstanding | shares						0	0	0
Common stock, par value (in dollars per share) | $ / shares						$ 0.0001	$ 0.0001	$ 0.0001
Proceeds from issuance of common stock and warrants							$ 99,547,283	$ 32,555,738
Change in fair value of warrant liability							3,915,393	$ (3,644,601)
Gain on warrant exchange							$ 2,228,697
Exercise of warrants | shares								78,431
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
Issuance of shares | shares								4,889
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				$ 300,000		$ (3,600,000)
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 Exchange Agreements [Member] | Stock Price [Member] | Class Of Warrant Or Right Issued on April 2019 [Member] | Warrant [Member]
Stockholders Equity [Line Items]
Fair value assumptions		0.0170
Warrant Exchange Agreements [Member] | Stock Price [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | Warrant [Member]
Stockholders Equity [Line Items]
Fair value assumptions		0.0164
Warrant Exchange Agreements [Member] | Volatility [Member] | Class Of Warrant Or Right Issued on April 2019 [Member] | Warrant [Member]
Stockholders Equity [Line Items]
Fair value assumptions		0.73
Warrant Exchange Agreements [Member] | Volatility [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | Warrant [Member]
Stockholders Equity [Line Items]
Fair value assumptions		0.73
Warrant Exchange Agreements [Member] | Remaining Term [Member] | Class Of Warrant Or Right Issued on April 2019 [Member] | Warrant [Member]
Stockholders Equity [Line Items]
Fair value assumptions		3 years 10 months 13 days
Warrant Exchange Agreements [Member] | Remaining Term [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | Warrant [Member]
Stockholders Equity [Line Items]
Fair value assumptions		3 years 10 months 13 days
Warrant Exchange Agreements [Member] | Risk-free Interest Rate [Member] | Class Of Warrant Or Right Issued on April 2019 [Member] | Warrant [Member]
Stockholders Equity [Line Items]
Fair value assumptions		0.0028
Warrant Exchange Agreements [Member] | Risk-free Interest Rate [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | Warrant [Member]
Stockholders Equity [Line Items]
Fair value assumptions		0.0027
Warrant Exchange Agreements [Member] | Discount for Lack of Marketability [Member] | Class Of Warrant Or Right Issued on May 2020 [Member] | Warrant [Member]
Stockholders Equity [Line Items]
Fair value assumptions		0.07
Securities Purchase Agreement [Member] | Warrant [Member]
Stockholders Equity [Line Items]
Common stock purchase warrants outstanding and exercisable | shares						3,074,551	3,074,551	8,907,884
Common Stock [Member] | Class Of Warrant Or Right Issued on April 2019 [Member]
Stockholders Equity [Line Items]
Exercise price | $ / shares						$ 1.80	$ 1.80
Common Stock [Member] | Share Exchange Agreements [Member]
Stockholders Equity [Line Items]
Number of shares issued upon new issue | shares		2,406,250
Warrant [Member]
Stockholders Equity [Line Items]
Exercise of warrants | shares								78,431
Issuance of shares | shares								4,889
Warrant [Member] | Stock Price [Member] | Class Of Warrant Or Right Issued on April 2019 [Member]
Stockholders Equity [Line Items]
Fair value assumptions								0.0110
Warrant [Member] | Stock Price [Member] | Class Of Warrant Or Right Issued on May 2020 [Member]
Stockholders Equity [Line Items]
Fair value assumptions						0.0178	0.0178
Warrant [Member] | Volatility [Member] | Class Of Warrant Or Right Issued on April 2019 [Member]
Stockholders Equity [Line Items]
Fair value assumptions								0.60
Warrant [Member] | Volatility [Member] | Class Of Warrant Or Right Issued on May 2020 [Member]
Stockholders Equity [Line Items]
Fair value assumptions						0.78	0.78
Warrant [Member] | Remaining Term [Member] | Class Of Warrant Or Right Issued on April 2019 [Member]
Stockholders Equity [Line Items]
Fair value assumptions								4 years 3 days
Warrant [Member] | Remaining Term [Member] | Class Of Warrant Or Right Issued on May 2020 [Member]
Stockholders Equity [Line Items]
Fair value assumptions						3 years 3 days	3 years 3 days
Warrant [Member] | Risk-free Interest Rate [Member] | Class Of Warrant Or Right Issued on April 2019 [Member]
Stockholders Equity [Line Items]
Fair value assumptions								0.0033
Warrant [Member] | Risk-free Interest Rate [Member] | Class Of Warrant Or Right Issued on May 2020 [Member]
Stockholders Equity [Line Items]
Fair value assumptions						0.0035	0.0035
Securities Purchase Agreement [Member] | Common Stock [Member]
Stockholders Equity [Line Items]
Number of shares issued upon new issue | shares							40,000,000	10,000,000
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]
Common stock price per share | $ / shares			$ 2.00
Number of shares issued upon new issue | shares			10,000,000
Proceeds from issuance of common stock			$ 20,000,000
Securities Purchase Agreement [Member] | Eagle Pharmaceuticals, Inc [Member] | Series A Preferred Stock [Member]
Stockholders Equity [Line Items]
Shares designated and reserved for future issuance | shares			10,000
Stock conversion ratio equal to quotient of $1,000			1.15
Threshold trading days for computation of weighted average price on conversion of stock | TradingDay			7
Underwritten Registered Offering [Member]
Stockholders Equity [Line Items]
Common stock purchase warrants | shares					8,000,000
Common stock, par value (in dollars per share) | $ / shares					$ 0.0001
Proceeds from issuance of common stock and warrants					$ 11,300,000
Exercise price | $ / shares					$ 2.00
Warrants issued for common stock dividends					1
Underwritten Registered Offering [Member] | Common Stock [Member]
Stockholders Equity [Line Items]
Common stock price per share | $ / shares					$ 1.50
Number of shares issued upon new issue | shares								8,000,000
Underwritten Registered Offering [Member] | Maximum [Member]
Stockholders Equity [Line Items]
Number of shares that can be purchased with warrants | shares					8,000,000
Sale Agreement [Member] | Jefferies [Member]
Stockholders Equity [Line Items]
Payment of commission rate from gross proceeds				3.00%
Proceeds from issuance of common stock							$ 6,100,000	$ 1,700,000
Available for offering						$ 22,200,000	$ 22,200,000
Sale Agreement [Member] | Jefferies [Member] | Maximum [Member]
Stockholders Equity [Line Items]
Aggregate offering				$ 30,000,000
Jefferies [Member] | Sale Agreement [Member]
Stockholders Equity [Line Items]
Number of shares issued upon new issue | shares							4,453,939	1,361,315
Proceeds from issuance of common stock							$ 6,100,000	$ 1,700,000
Related cost offset the proceeds							300,000	$ 200,000
Available for offering						$ 22,200,000	$ 22,200,000
Registered Direct Offering [Member]
Stockholders Equity [Line Items]
Proceeds from issuance of common stock	$ 100,000,000
Related cost offset the proceeds	$ 6,200,000
Registered Direct Offering [Member] | Common Stock [Member]
Stockholders Equity [Line Items]
Common stock, par value (in dollars per share) | $ / shares	$ 0.0001
Common stock price per share | $ / shares	$ 2.50
Number of shares issued upon new issue | shares	40,000,000