Intangible Assets and Goodwill (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Dec. 31, 2016
Intangible Assets and Goodwill
Changes to carrying amount of goodwill		$ 0
Finite-lived intangible asset
Accumulated Amortization	$ (7,175,000)	(7,175,000)	$ (6,503,000)
Total Intangible Assets
Gross carrying amount of total intangible assets, net	74,990,000	74,990,000	87,990,000
Net carrying amount of total intangible assets, net	67,815,000	67,815,000	81,487,000
In-Process Research and Development Impairment	13,000,000	$ 13,000,000
License Rights
Finite-lived intangible asset
Estimated Life		16 years
Gross carrying amount finite-lived	14,500,000	$ 14,500,000	14,500,000
Accumulated Amortization	(7,175,000)	(7,175,000)	(6,503,000)
Net carrying amount finite-lived	7,325,000	7,325,000	7,997,000
IPR&D
Indefinite-lived intangible assets:
Gross carrying amount of indefinite-lived	60,490,000	60,490,000	73,490,000
Net carrying amount of indefinite-lived	60,490,000	60,490,000	$ 73,490,000
Kolltan | IPR&D
Total Intangible Assets
In-Process Research and Development Impairment	$ 13,000,000	$ 13,000,000