Acquisition of Callidus Biopharma, Inc. (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended			1 Months Ended	6 Months Ended		1 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Nov. 30, 2013 Callidus	Jun. 30, 2014 Callidus	Dec. 31, 2013 Callidus	Nov. 30, 2013 Callidus Maximum
Acquisition of Callidus Biopharma, Inc.
Common stock issued on acquisition (in shares)						7,200	25
Common stock, par value (in dollars per share)	$ 0.01		$ 0.01		$ 0.01	$ 0.01
Additional payment to be made upon achievement of clinical milestone									$ 35,000,000
Additional payment to be made upon achievement of regulatory approval									105,000,000
Maximum merger consideration to be transferred						130,000,000
Milestone payment that can be settled in equity						40,000,000
Number of trading days immediately preceding the date of payment on basis of which issue price will be determined						10 days
Discount rate (as a percent)						13.00%
Increase in the contingent consideration payable	(305,000)		200,000				200,000
Contingent acquisition consideration payable	10,800,000		10,800,000		10,600,000	10,600,000	10,800,000	10,600,000
Intangible assets-(IPR&D)							23,000,000
Deferred tax liability							9,200,000
Goodwill expected to be deductible for income tax purposes							0
Supplemental Pro Forma Information
Net Loss		$ 15,891,000		$ 33,731,000