Changes in Carrying Amount of Intangible Assets (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Goodwill [Line Items]
Intangible asset carrying amount, beginning balance	$ 14,524,500		$ 14,524,500		$ 14,524,500
Intangible asset carrying amount, Amortization	513,868	446,218	1,027,735	896,960
Intangible asset carrying amount, ending balance	14,524,500		14,524,500		14,524,500
Intangible asset accumulated amortization, beginning balance			(3,385,879)
Intangible asset, accumulated amortization			(1,027,735)
Intangible asset accumulated amortization, ending balance	(4,413,614)		(4,413,614)
Intangible asset beginning balance, net			11,138,621
Intangible asset amortization, net	(513,868)	(446,218)	(1,027,735)	(896,960)
Intangible asset ending balance, net	$ 10,110,886		$ 10,110,886