Accrued Liabilities (Detail) (USD $)	Jun. 30, 2013	Dec. 31, 2012
Schedule of Accrued Liabilities [Line Items]
Royalties	$ 164,602	$ 351,846
Interest	179,537	0
Payroll	72,004	77,757
Miscellaneous	4,914	16,831
Total accrued liabilities	596,107	446,434
Redeemable Preferred Stock
Schedule of Accrued Liabilities [Line Items]
10% convertible preferred stock dividend	$ 175,050	$ 0