Warrants - Additional Information (Detail) - USD ($)	1 Months Ended	6 Months Ended
Aug. 11, 2020	Jun. 30, 2020	Jun. 30, 2019
Net proceeds from warrant exercises		$ 31,310,137	$ 30,324
Subsequent Event [Member]
Net proceeds from warrant exercises	$ 9,600,000
Number of warrants exercised	1,983,110
Public Offering [Member] \| Subsequent Event [Member]
Pre-funded warrants issued	1,630,436

The cash inflow associated with the amount received from holders exercising their stock warrants.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

Name:	us-gaap_ProceedsFromWarrantExercises
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration