Major Customers, Partnerships and Strategic Alliances (Tables)

3 Months Ended

Mar. 31, 2014

Shire AG [Member]

Revenues Recognized under Agreement

Revenues recognized under the agreement with Shire for the three ended March 31, 2014 and 2013, were as follows (in thousands):

	Three months ended March 31,
	2014		2013
Revenue related to Shire Collaboration:
Recognition of upfront fee	$	542	$	542
Research services		4,979		3,214
Total	$	5,521	$	3,756

Sigma-Aldrich Corporation [Member]

Revenues Recognized under Agreement

Revenues recognized under the agreement with Sigma for the three months ended March 31, 2014 and 2013, were as follows (in thousands):

	Three months ended March 31,
	2014		2013
Revenue related to Sigma Collaboration:
Royalty revenues	$	106	$	314
License fee and milestone revenues		179		—
Total	$	285	$	314

Biogen [Member]

Revenues Recognized under Agreement

Revenues recognized under the agreement with Biogen for the three months ended March 31, 2014 are as follows (in thousands):

	Three months ended March 31,
	2014
Revenue related to Biogen Collaboration:
Recognition of upfront fee	$	660
Research services		423
Total	$	1,083