Property and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2012

Property and Equipment, Net

Schedule of property and equipment

	December 31,
(in thousands)	2011			2012
Lab equipment	$	11,757		$	12,616
IT equipment		2,204			2,346
Leasehold improvements		7,698			8,200
Furniture and fixtures		329			330
Construction in process		348			1,774
		22,336			25,266
Less: Accumulated depreciation and amortization		(16,130	)		(18,969	)
	$	6,206		$	6,297