Investment - Summary of Available-for-Sale Investments by Security type (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Net Investment Income [Line Items]
Amortized cost	$ 64,929,745	$ 15,409,355
Gross Unrealized Gains	9,505
Gross Unrealized Losses	0	(20,248)
Estimated Fair Value	64,939,250	15,389,107
U.S. Treasuries - ST [Member]
Net Investment Income [Line Items]
Amortized cost		10,382,699
Gross Unrealized Losses		(1,835)
Estimated Fair Value		10,380,864
U.S. Treasuries - LT [Member]
Net Investment Income [Line Items]
Amortized cost	4,999,587	5,026,656
Gross Unrealized Gains	7,463
Gross Unrealized Losses	0	(18,413)
Estimated Fair Value	5,007,050	$ 5,008,243
US Treasury Bond Securities Cash Equivalents [Member]
Net Investment Income [Line Items]
Amortized cost	59,930,158
Gross Unrealized Gains	2,042
Gross Unrealized Losses	0
Estimated Fair Value	$ 59,932,200