Stock-Based Compensation

9 Months Ended

Sep. 30, 2015

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

2.	STOCK-BASED COMPENSATION

Total stock-based compensation expense was allocated to research and development, manufacturing and production and general and administrative expense as follows (in thousands):

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2015		2014		2015		2014
Research and development	$	93	$	186	$	309	$	628
Manufacturing and production		42		56		123		177
General and administrative		302		488		1,102		1,646
Total stock-based compensation expense	$	437	$	730	$	1,534	$	2,451

During the nine months ended September 30, 2015 and 2014, the Company granted stock-based awards with a total estimated value of $1.9 million and $2.3 million, respectively. At September 30, 2015, total unrecognized estimated compensation expense related to unvested stock-based awards granted prior to that date was $1.7 million, which is expected to be recognized over a weighted-average period of 1.4 years. Stock-based awards granted during the nine months ended September 30, 2015 and 2014, were equal to 3.3% and 3.0%, respectively, of the outstanding shares of common stock at the end of the applicable period.