Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes Disclosure [Line Items]
Benefit attributable to reduction in allowance against certain deferred tax assets		$ 0	$ 0	$ (15,217,000)
Deferred tax benefit				346,000
Net deferred tax asset		18,429,737	22,436,737
Aggregate Federal NOL carryforwards		46,018,000
Federal NOLs subject to an annual limitation		13,300,000
Federal NOLs not subject to an annual limitation		32,718,000
Federal NOLs annual limitation		2,779,000
Aggregate Federal NOLs expiring		10,672,000
Federal NOL attributable to excess tax deductions		$ 1,723,000
Expirations of NOL		2024
Valuation allowance		$ 0	0	0
Aggregate income tax payments		651,502	229,982	723,228
Unrecognized tax benefits and the related estimate for interest and penalties		159,000	105,000	62,000	$ 345,000
Additional general and administrative expense, including interest		$ 70,000	$ 43,000	$ 51,000
New York State and New York City [Member]
Income Taxes Disclosure [Line Items]
Aggregate income tax payments	$ 16,000