Goodwill and Intangible Assets - Gross Carrying Amounts and Net Book Values of Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 1,506,030	$ 1,491,768
Accumulated Amortization	(450,980)	(421,687)
Total	1,055,050	1,070,081
Indefinite-lived Intangible Assets [Line Items]
Gross Carrying Amount - Total Intangible Assets	3,449,760	3,433,688
Net Book Value - Total Intangible Assets	2,998,780	3,012,001
Acquired in-process research and development assets
Indefinite-lived Intangible Assets [Line Items]
In-process research and development	$ 1,943,730	1,941,920
Acquired developed technologies
Finite-Lived Intangible Assets [Line Items]
Remaining Weighted-Average Useful Life (in years)	11 years 1 month 6 days
Gross Carrying Amount	$ 1,491,720	1,477,618
Accumulated Amortization	(438,983)	(410,523)
Total	$ 1,052,737	1,067,095
Manufacturing contracts
Finite-Lived Intangible Assets [Line Items]
Remaining Weighted-Average Useful Life (in years)	9 months 18 days
Gross Carrying Amount	$ 11,434	11,278
Accumulated Amortization	(9,121)	(8,292)
Total	$ 2,313	2,986
Trademarks
Finite-Lived Intangible Assets [Line Items]
Remaining Weighted-Average Useful Life (in years)	0 years
Gross Carrying Amount	$ 2,876	2,872
Accumulated Amortization	(2,876)	(2,872)
Total	$ 0	$ 0