Collaboration Revenue (Tables)

6 Months Ended

Jun. 30, 2013

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Summary of Deferred Revenue

Deferred revenue consists of the following:

	June 30, 2013		December 31, 2012
Upfront and milestone payments	$	61,814	$	51,359
Prepaid research and development services		2,819		7,229
Other		46		48
Total	$	64,679	$	58,636
Current portion of deferred revenue		8,270		9,963
Long-term portion of deferred revenue		56,409		48,673
Total	$	64,679	$	58,636