Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Allowance for Doubtful Accounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 25,000	$ 25,000
Charged to costs and expenses	8,374	1,901
Charged to other accounts	0	0
Recoveries/ (Deductions)	(8,374)	(1,901)
Balance at End of Period	25,000	25,000
Deferred Tax Asset Valuation Allowance
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	49,274,154	43,660,035
Charged to costs and expenses	3,175,637	5,867,273
Charged to other accounts	0	0
Recoveries/ (Deductions)	(17,118,477)	(253,154)
Balance at End of Period	$ 35,331,314	$ 49,274,154