Accounts Payable and Accrued Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Accounts Payable and Accrued Liabilities [Line Items]
Trade accounts payable	$ 1,081	$ 1,127
Accrued royalties	87	87
Accrued interest	213	154
Sales taxes payable	85	78
Accrued compensation	91	80
Other accrued expenses	39	108
Total	$ 1,596	$ 1,634