Schedule of Accrued Liabilities (Detail) (USD $)	Mar. 31, 2013	Dec. 31, 2012
Schedule of Accrued Liabilities [Line Items]
Employee compensation	$ 2,559,183	$ 3,634,839
Royalty and license fees	968,716	1,459,680
Contingent consideration	1,092,821	1,376,877
Unearned revenue	550,498	599,120
Professional fees	332,792	418,800
VAT liabilities	186,180	98,162
Research and development	32,585	18,300
Other accrued expenses	1,271,030	692,212
Total	$ 6,993,805	$ 8,297,990