Collaborative and Other Relationships Collaborative and Other Relationships - Collaboration Agreement (Details) (USD $) In Millions, unless otherwise specified		3 Months Ended	1 Months Ended
Mar. 31, 2014 Eisai	Mar. 31, 2014 Sangamo BioSciences	Jan. 31, 2014 Isis Pharmaceuticals	Mar. 31, 2014 Research and development Eisai
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Total upfront and milestone payments	$ 100.0	$ 20.0
Amount recorded to reflect fair value of options granted				17.7
Research and development expense		20.0	45.0
Additional milestone payment	$ 1,000.0	$ 300.0

- Definition

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

+ References+ Details