XML 75 R60.htm IDEA: XBRL DOCUMENT

Stock-Based Compensation Expense (Detail) (USD $)	9 Months Ended		12 Months Ended
Stock-Based Compensation Expense (Detail) (USD $)	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 616,000	$ 166,000	$ 221,000	$ 299,000	$ 345,000
General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	303,000	69,000	93,000	152,000	170,000
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 313,000	$ 97,000	$ 128,000	$ 147,000	$ 175,000

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References+ Details