Subsequent Events	3 Months Ended
Mar. 31, 2013
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events In April 2013, the Company entered into a Royalty Stream and Milestone Payments purchase agreement with Selexis SA ("Selexis"), a privately held life sciences company, to acquire a portfolio of possible future royalty and milestone payment rights based on over 15 Selexis commercial license agreement programs with various pharmaceutical-company counterparties. In return, the Company paid Selexis $3.5 million in an upfront cash payment, and will pay an additional $1 million cash payment on the first anniversary of the closing. The more than 15 programs that are the subject of this transaction are based on Selexis' technology platform for cell line development and scale-up to manufacturing of therapeutic proteins and relate to pre-commercialized drugs that are currently being developed, and which should require no funding or technological support from the Company.

Subsequent Events

3 Months Ended

Mar. 31, 2013

In April 2013, the Company entered into a Royalty Stream and Milestone Payments purchase agreement with Selexis SA ("Selexis"), a privately held life sciences company, to acquire a portfolio of possible future royalty and milestone payment rights based on over 15 Selexis commercial license agreement programs with various pharmaceutical-company counterparties. In return, the Company paid Selexis $3.5 million in an upfront cash payment, and will pay an additional $1 million cash payment on the first anniversary of the closing. The more than 15 programs that are the subject of this transaction are based on Selexis' technology platform for cell line development and scale-up to manufacturing of therapeutic proteins and relate to pre-commercialized drugs that are currently being developed, and which should require no funding or technological support from the Company.