Capitalized Fees Paid to a Related Party (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Capitalized Fees paid to a Related Party
Net Carrying Value	$ 194,368	$ 208,191
Amortization of capitalized fees paid to a related party	13,823	11,066	$ 743
Estimated amortization expense for the year 2016	13,800
Estimated amortization expense for the year 2017	13,800
Estimated amortization expense for the year 2018	13,800
Estimated amortization expense for the year 2019	13,800
Estimated amortization expense for the year 2020	13,800
Estimated amortization expense thereafter	125,300
GSK
Capitalized Fees paid to a Related Party
Amortization of capitalized fees paid to a related party	$ 13,823	11,066	$ 743
GSK | LABA Collaboration
Capitalized Fees paid to a Related Party
Weighted Average Remaining Amortization Period	14 years 1 month 6 days
Gross Carrying Value	$ 220,000	220,000
Accumulated Amortization	(25,632)	(11,809)
Net Carrying Value	$ 194,368	$ 208,191