Other Accrued Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Other Liabilities [Line Items]
Professional fees	$ 259	$ 311
Commercialization costs	469	159
Government rebates	118	78
Legal fees	77	31
Other	35	116
Other accrued liabilities	$ 958	$ 695