Collaborative Arrangements and Licensing Agreements, External Project Funding (Details) - USD ($)	1 Months Ended	3 Months Ended								12 Months Ended
	Aug. 31, 2016	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015		Dec. 31, 2014	Dec. 31, 2013
Collaborative Arrangement and Licensing Agreement [Abstract]
Research and development expense										$ 340,400,000	$ 319,500,000		$ 238,900,000
Revenue earned		$ 160,349,000	$ 110,927,000	$ 38,470,000	$ 36,874,000	$ 51,571,000	$ 49,121,000	$ 120,428,000	$ 62,583,000	346,620,000	283,703,000		214,161,000
CHDI Foundation, Inc. [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Research and development expense											5,000,000			$ 3,000,000
Maximum amount of payments payable for pre-specified milestones		4,000,000								4,000,000
Revenue earned										0	$ 0	[1]	$ 0
Cystic Fibrosis Foundation [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned										600,000
Upfront payment recorded as deferred revenue	$ 1,000,000
Maximum amount of payments receivable		2,000,000								2,000,000
Maximum costs specific to collaboration to be shared evenly with partner		3,000,000								3,000,000
Maximum amount of payments payable for regulatory and commercialization milestones		18,000,000								18,000,000
Next prospective milestone		$ 500,000								$ 500,000

[1] Revenue from this relationship was negligible for the year.