Acquisition of Callidus Biopharma, Inc. (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended		146 Months Ended		1 Months Ended	3 Months Ended	12 Months Ended	1 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Dec. 31, 2013	Nov. 30, 2013 Callidus	Mar. 31, 2014 Callidus	Dec. 31, 2013 Callidus	Nov. 30, 2013 Callidus Maximum
Acquisition of Callidus Biopharma, Inc.
Common stock issued on acquisition (in shares)					7.2	25.0
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)					13.50%
Increase in the contingent consideration payable	505,000		505,000			505,000
Allocation of the purchase consideration, including the contingent acquisition consideration payable
Upfront equity payments						15,000,000
Contingent acquisition consideration payable	11,105,000		11,105,000	10,600,000	10,600,000	11,105,000	10,600,000
Total consideration						25,600,000
Cash and cash equivalents						34,000
Property, plant and equipment						173,000
Intangible assets-(IPR&D)						23,000,000
Total identifiable assets acquired						23,207,000
Accounts payable						(34,000)
Deferred tax liability						(9,186,000)
Total liabilities assumed						(9,220,000)
Net identifiable assets acquired						13,987,000
Goodwill	11,613,000		11,613,000	11,613,000		11,613,000
Net assets acquired						25,600,000
Deferred tax liabilities relates to the tax impact of future amortization or possible impairments associated with identified intangible assets acquired					9,200,000
Acquisition-related transaction costs							500,000
Supplemental Pro Forma Information
Net loss		$ 17,839,000