Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2015

Accounting Policies [Abstract]

Percentage of Revenue from Significant Customers

Customers who accounted for 10% or more of total revenues were as follows:

	Three Months Ended March 31,
	2015			2014
Bristol-Myers Squibb Company and Pfizer Inc.		16	%		19	%
Bayer Pharma, AG and Janssen Pharmaceuticals, Inc.		34	%		38	%
Daiichi Sankyo, Inc.		48	%		40	%