Subsequent Event (Details) - Subsequent Event - Scenario, Forecast [Member] - Kolltan Pharmaceuticals $ in Millions	Nov. 01, 2016 USD ($) shares
Subsequent Event
Number of common stock shares issued | shares	19,218,942
Value of Shares, based on average closing price | $	$ 62.5
Days used for comparable average closing price	5 days
Maximum percentage issued shares can fluctuate	0.05
Ending day of comparable average closing prices	3 days
Shares issued in lieu of cash severance obligations | shares	461,000
Maximum amount of milestone payments | $	$ 172.5
Threshold of stock issuance which would require stockholder approval (percentage)	19.9
Percentage of Kolltan's shareholders required to approve	0.60