Warrants - Schedule Of Fair Value Of Warrant Liability (Detail)	Dec. 31, 2020 USD ($) shares	Dec. 31, 2020 $ / shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 shares	Apr. 30, 2018 $ / shares
Class of Warrant or Right [Line Items]
Strike Price | $ / shares					$ 7.75
Warrants Outstanding	2,520,794		2,406,811	0
Liability Classified Warrant [member]
Class of Warrant or Right [Line Items]
Warrants Outstanding	2,485,794		2,406,811
Warrant Liability | $	$ 39,454,000		$ 15,879,843
Bridge Financing Warrants [member] | Liability Classified Warrant [member]
Class of Warrant or Right [Line Items]
Strike Price | $ / shares		$ 22.90
Warrants Outstanding	218,964
Warrant Liability | $	$ 2,544,500		1,385,400
Private Placement Financing Warrants [member] | Liability Classified Warrant [member]
Class of Warrant or Right [Line Items]
Strike Price | $ / shares		19.39
Warrants Outstanding	1,822,771
Warrant Liability | $	$ 28,756,500		12,189,169
Modification Warrants [member] | Liability Classified Warrant [member]
Class of Warrant or Right [Line Items]
Strike Price | $ / shares		12.04
Warrants Outstanding	360,256
Warrant Liability | $	$ 6,630,000		$ 2,305,274
Additional Modification Warrants [member] | Liability Classified Warrant [member]
Class of Warrant or Right [Line Items]
Strike Price | $ / shares		$ 14.03
Warrants Outstanding	83,803
Warrant Liability | $	$ 1,523,000