Fair Value Measurement and Fair Value of Financial Instruments - Carrying Amounts and Fair Values of Company's Debt Obligations (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Carrying amount and fair value of the company's debt obligations
Subordinated notes payable	$ 4,000,000	$ 4,000,000
Carrying Value [Member]
Carrying amount and fair value of the company's debt obligations
Long-term debt, net of debt discount	4,900,318	6,370,413
Debt discount	99,682	129,587
Subordinated notes payable	4,000,000	4,000,000
Related party subordinated notes payable	2,000,000	2,000,000
Total debt obligations	11,000,000	12,500,000
Fair Value [Member]
Carrying amount and fair value of the company's debt obligations
Long-term debt, net of debt discount	4,900,318	6,370,413
Debt discount	99,682	129,587
Subordinated notes payable	4,000,000	4,000,000
Related party subordinated notes payable	2,000,000	2,000,000
Total debt obligations	$ 11,000,000	$ 12,500,000