Stockholders' Equity - Summary of Stock-Based Compensation Expense (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Stockholders Equity [Line Items]
Stock-based compensation	$ 487,403	$ 564,024	$ 1,758,315	$ 1,951,317
Research and Development
Stockholders Equity [Line Items]
Stock-based compensation	115,817	166,289	606,470	785,423
General and Administrative
Stockholders Equity [Line Items]
Stock-based compensation	$ 371,586	$ 397,735	$ 1,151,845	$ 1,165,894

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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