Annual report pursuant to Section 13 and 15(d)

Capital Structure - Additional Information (Detail)

Capital Structure - Additional Information (Detail)							12 Months Ended
Capital Structure - Additional Information (Detail)	May 27, 2020 USD ($) $ / shares shares	Dec. 18, 2019 USD ($) $ / shares shares	Dec. 12, 2019 USD ($) $ / shares shares	Aug. 03, 2018 USD ($) $ / shares shares	Jul. 25, 2017 USD ($) shares	Jul. 27, 2016 USD ($) shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares	Dec. 31, 2018 USD ($)
Class of Stock [Line Items]
Common stock, shares authorized \| shares							125,000,000
Common stock, par value \| $ / shares							$ 0.0001	$ 0.0001
Number of shares issued \| shares	11,797,752	2,565,000	3,715,000
Public offering price, per unit \| $ / shares		$ 3.90	$ 2.70
Net proceeds received	$ 48,900,000
Gross Proceed	$ 3,000,000	$ 10,000,000	$ 13,000,000
Dividends declared or paid							$ 0
Combined Net Proceeds			$ 21,300,000
Aggregate gross sales proceeds from common stock							55,499,990	$ 23,034,000	$ 11,500,000
Issuance costs allocated to warrants							$ 2,174,653
Common stock, voting rights							The holders of shares of common stock are entitled to one vote for each share of common stock held at all meetings of stockholders and written actions in lieu of meetings.
Issuance of common stock for exercise of warrants, Shares \| shares							5,850
Private Placement [Member]
Class of Stock [Line Items]
Public offering price, per unit \| $ / shares	$ 4.45		$ 2.70
Issuance of securities in private placement, Shares \| shares	674,156		1,111,111
Follow-on Offering [Member]
Class of Stock [Line Items]
Number of shares issued \| shares	11,797,752			575,000	3,200,000	1,400,000
Public offering price, per unit \| $ / shares	$ 4.45			$ 20.00
Net proceeds received	$ 48,900,000			$ 10,400,000	$ 37,100,000	$ 32,000,000
Warrants to purchase shares of common stock \| shares	8,848,314
Aggregate gross sales proceeds from common stock				$ 11,500,000	$ 40,000,000	$ 35,000,000
Warrant exercise price per share \| $ / shares	$ 4.90
Conversion ratio of common stock							0.75
Follow-on Offering [Member] \| CMPO Warrants [Member]
Class of Stock [Line Items]
Warrants to purchase shares of common stock \| shares					1,600,000	1,400,000
Follow-on Offering [Member] \| 2016 Warrants [Member]
Class of Stock [Line Items]
Fair value of warrants						$ 18,600,000
Issuance costs allocated to warrants						$ 1,600,000
Follow-on Offering [Member] \| 2017 Warrants [Member]
Class of Stock [Line Items]
Fair value of warrants					$ 12,400,000
Issuance costs allocated to warrants					$ 900,000
Follow-on Offering [Member] \| 2020 Warrants [Member]
Class of Stock [Line Items]
Fair value of warrants	$ 31,400,000
Issuance costs allocated to warrants	$ 2,200,000
Pfizer Warrants [Member]
Class of Stock [Line Items]
Warrants to purchase shares of common stock \| shares	505,617
Warrant exercise price per share \| $ / shares	$ 4.90