Fair Value of Financial Instruments - Schedule of Cash Equivalents and Derivative Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	$ 8,730,149
Derivative liabilities	157,927	$ 3,661
In Active Markets for Identical Assets or Liabilities (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	8,730,149
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	$ 157,927