Summary of Significant Accounting Policies - Summary of Impact of New Standard on Consolidated Statement of Operations and Balance Sheet (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Jan. 01, 2018	Dec. 31, 2017
Revenue
Subscription revenue	$ 11,520,201	$ 11,429,089	$ 23,077,356	$ 23,008,451
Other revenue	463,693	280,131	686,193	826,723
Total revenue	11,983,894	11,709,220	23,763,549	23,835,174
Operating expenses
Sales and marketing	3,234,762	3,105,068	6,233,321	6,433,116
(Loss) income before income taxes	(580,003)	538,643	(976,104)	651,385
Income tax (benefit) expense	(121,000)	141,000	(165,000)	(281,000)
Net (loss)	$ (459,003)	$ 397,643	$ (811,104)	$ 932,385
Net (loss) per common share	$ (0.04)		$ (0.07)
ASSETS
Deferred tax asset, net	$ 11,683,895		$ 11,683,895		$ 11,483,895	$ 12,072,118
Other assets	3,238,422		3,238,422		3,327,633	217,161
Liabilities
Accrued expenses and other liabilities	4,825,408		4,825,408		4,832,654	4,149,363
Deferred revenue	25,890,104		25,890,104		26,558,707	26,533,983
Other long-term liabilities	2,531,017		2,531,017		2,580,952	2,447,037
Equity
Retained earnings (deficit)	(24,681,312)		(24,681,312)		(19,437,282)	$ (21,117,601)
Balances Without Adoption of ASU 2014-09 [Member]
Revenue
Subscription revenue	11,517,939		23,097,092
Other revenue	478,693		701,193
Total revenue	11,996,632		23,798,285
Operating expenses
Sales and marketing	3,128,080		6,050,909
(Loss) income before income taxes	(460,583)		(758,956)
Income tax (benefit) expense	(90,000)		(109,000)
Net (loss)	$ (370,583)		$ (649,956)
Net (loss) per common share	$ (0.03)		$ (0.06)
ASSETS
Deferred tax asset, net	$ 12,211,118		$ 12,211,118
Other assets	182,382		182,382
Liabilities
Accrued expenses and other liabilities	4,055,961		4,055,961
Deferred revenue	25,818,991		25,818,991
Other long-term liabilities	2,355,278		2,355,278
Equity
Retained earnings (deficit)	(23,168,794)		(23,168,794)
ASU 2014-09 [Member]
ASSETS
Deferred tax asset, net					(588,223)
Other assets					3,110,472
Liabilities
Accrued expenses and other liabilities					683,291
Deferred revenue					24,724
Other long-term liabilities					133,915
Equity
Retained earnings (deficit)					$ 1,680,319
ASU 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue
Subscription revenue	2,262		(19,736)
Other revenue	(15,000)		(15,000)
Total revenue	(12,738)		(34,736)
Operating expenses
Sales and marketing	106,682		182,412
(Loss) income before income taxes	(119,420)		(217,148)
Income tax (benefit) expense	(31,000)		(56,000)
Net (loss)	88,420		(161,148)
ASSETS
Deferred tax asset, net	(527,223)		(527,223)
Other assets	3,056,040		3,056,040
Liabilities
Accrued expenses and other liabilities	769,447		769,447
Deferred revenue	71,113		71,113
Other long-term liabilities	175,739		175,739
Equity
Retained earnings (deficit)	$ (1,512,518)		$ (1,512,518)