Intangible assets and goodwill (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($)
Finite-lived intangible assets:
Accumulated Amortization	$ 23,331
Intangible Assets, Net
Gross Carrying Amount	283,000
Net Carrying Amount	259,669
Amortization Expense
Remainder of 2017	10,768
2018	21,536
2019	21,536
2020	21,536
2021	21,536
Thereafter	150,757
Changes to carrying amount of goodwill
Changes to the carry amount of goodwill	0
IPR&D
Indefinite-lived intangible assets:
Net Carrying Amount	$ 12,000
Licensed IP
Intangible assets
Weighted Average Useful Lives (Years)	12 years 6 months
Finite-lived intangible assets:
Gross Carrying Amount	$ 271,000
Accumulated Amortization	23,331
Finite-Lived Intangible Assets, Net, Total	$ 247,669