License and Collaboration Agreements (Tables)

12 Months Ended

Dec. 31, 2013

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Schedule of Revenue Recognized and Assets and Liabilities under Collaborative Arrangements

During the years ended December 31, 2013, 2012 and 2011, the Company recognized revenue based on the following components of the Sanofi agreement:

	Years ended December 31,
(in thousands)	2013		2012		2011
Upfront payment	$	5,000	$	5,000	$	5,000
Milestone payment		2,083		2,975		2,616
Development services		36,283		36,905		25,053
Manufacturing services and other		3,867		3,307		1,456
Total	$	47,233		48,187	$	34,125

As of December 31, 2013 and 2012, the Company maintained the following assets and liabilities related to the Sanofi agreement:

	December 31,
(in thousands)	2013		2012
Accounts receivable, billed	$	2,357	$	1,577
Accounts receivable, unbilled		3,417		7,690
Deferred revenues		73,392		79,913