Components of Income Before Income Taxes and Provision for (Benefit from) Income Taxes (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
Domestic	$ 26,170,313	$ 15,962,992	$ 11,944,795
Foreign	(6,642,892)	(2,177,978)	(4,601,729)
Income before income taxes	19,527,421	13,785,014	7,343,066
Current provision:
Federal	7,594,287	3,327,626	1,063,841
State	885,958	155,855	(6,920)
Foreign	(188,650)	90,626
Current Income Tax Expense (Benefit), Total	8,291,595	3,574,107	1,056,921
Deferred provision:
Federal	776,486	1,907,408	2,828,029
State	602,447	570,869	479,529
Foreign	(1,900,567)	(734,050)	(1,337,408)
Net Deferred Income Tax Expense Benefit, Total	(521,634)	1,744,227	1,970,150
Total provision	$ 7,769,961	$ 5,318,334	$ 3,027,071