Basis of Presentation and Significant Accounting Policies - Fair Value Measurement Specific to Assets or Liability (Detail) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Short-Term Bond Fund [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments Fair Value Disclosure		$ 5,007,050
U.S. Treasuries [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 69,997,200	59,932,200
Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	23,610,888	23,963,617
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	23,610,888	23,963,617
Significant Other Observable Inputs (Level 2) [Member] | Short-Term Bond Fund [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments Fair Value Disclosure		5,007,050
Significant Other Observable Inputs (Level 2) [Member] | U.S. Treasuries [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 69,997,200	$ 59,932,200