Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2015

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Compensation Cost Related to Share-Based Awards

The Company has recognized the following compensation cost related to share-based awards:

	Three months ended				Six months ended
	June 30, 2015		June 30, 2014		June 30, 2015		June 30, 2014
	(in thousands)				(in thousands)
Research and development	$	397	$	961	$	962	$	1,906
General and administrative		698		483		1,261		1,983
Total	$	1,095	$	1,444	$	2,223	$	3,889

Schedule of Compensation Expense by Type of Award

Compensation expense by type of award:

	Three months ended				Six months ended
	June 30, 2015		June 30, 2014		June 30, 2015		June 30, 2014
	(in thousands)				(in thousands)
Stock options	$	908	$	491	$	1,607	$	776
Restricted stock		142		953		542		3,113
Restricted stock units		24		—		32		—
Employee stock purchase plan		21		—		42		—
Total	$	1,095	$	1,444	$	2,223	$	3,889