Collaborative Arrangements (Details) (USD $)	3 Months Ended								12 Months Ended			1 Months Ended	12 Months Ended	1 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Apr. 30, 2011	Dec. 31, 2006	Oct. 31, 2014	Nov. 30, 2013
Collaborative revenues:
Royalty revenues	$ 8,785,000	$ 8,386,000	$ 13,015,000	$ 10,733,000	$ 36,887,000	$ 27,012,000	$ 49,120,000	$ 43,573,000	$ 40,919,000	$ 156,592,000	$ 141,498,000
Collaborative revenues	10,829,000	33,502,000	3,087,000	4,257,000	185,448,000	8,035,000	6,841,000	17,414,000	51,675,000	217,738,000	52,086,000
Total revenues	144,556,000	178,987,000	138,421,000	118,451,000	351,157,000	221,700,000	310,750,000	328,368,000	580,415,000	1,211,975,000	1,527,042,000
Intangible asset impairment charges					0	0	0	412,900,000	0	412,900,000	0
Noncontrolling Interest (Alios)
Provision for (benefit from) income taxes	2,043,000	3,419,000	693,000	803,000	1,352,000	2,555,000	558,000	(126,887,000)	6,958,000	(122,422,000)	(275,000)
Net loss (income) attributable to noncontrolling interest (Alios)	(4,190,000)	0	0	0
Income (Loss) from Continuing Operations Attributable to Noncontrolling Interest									(4,190,000)	0	0
Noncontrolling interest	21,177,000				0				21,177,000	0
Collaborative revenues	10,829,000	33,502,000	3,087,000	4,257,000	185,448,000	8,035,000	6,841,000	17,414,000	51,675,000	217,738,000	52,086,000
Cystic Fibrosis Foundation Therapeutics Incorporated
Schedule of Collaborative Arrangements
Collaborative funding												75,000,000
Number of years over which funding will be made (in years)												5 years
Milestone payments										9,300,000	9,300,000
Number of commercial milestone payments for achievement of certain sales levels for corrector compound such as VX-809 or VX-661 (in payments)									2
Collaborative revenues:
Collaborative revenues									6,500,000	14,300,000	17,000,000
Noncontrolling Interest (Alios)
Collaborative revenues									6,500,000	14,300,000	17,000,000
Janssen
Schedule of Collaborative Arrangements
Drug development costs to be paid by collaborator (percent)													50.00%
Up-front license payment	5,000,000	30,000,000											165,000,000
Deferred revenue related to up-front license payment															32,100,000
Tiered royalty average range, as a percentage of net sales in the Janssen territories									20.00%
License fee paid upon amendment of agreement					152,000,000
Collaborative revenues:
Royalty revenues									13,481,000	130,724,000	117,592,000
Up-front and amendment payments revenues									0	190,345,000	12,428,000
Net reimbursement (payment) for telaprevir development costs									7,104,000	2,793,000	(3,507,000)
Reimbursement for manufacturing services									0	10,299,000	7,257,000
Collaborative revenues					182,400,000				7,104,000	203,437,000	16,178,000
Total revenues									20,585,000	334,161,000	133,770,000
Noncontrolling Interest (Alios)
Collaborative revenues					182,400,000				7,104,000	203,437,000	16,178,000
Reimbursement for research and development activities									9,100,000
Mitsubishi Tanabe
Collaborative revenues:
Collaborative revenues									0	0	18,900,000
Noncontrolling Interest (Alios)
Collaborative revenues									0	0	18,900,000
Alios BioPharma, Inc
Noncontrolling Interest (Alios)
Loss before provision for (benefit from) income taxes										283,747,000	20,044,000
Decrease (increase) in fair value of contingent milestone and royalty payments										124,920,000	(114,970,000)
Provision for (benefit from) income taxes										(166,145,000)	39,029,000
Net loss (income) attributable to noncontrolling interest (Alios)										242,522,000	(55,897,000)
Contingent consideration payable					0					0
BioAxone Biosciences, Inc
Schedule of Collaborative Arrangements
Up-front license payment	10,000,000
Noncontrolling Interest (Alios)
Maximum license fees and milestone payments														90,000,000
Contingent consideration payable														26,600,000
Noncontrolling interest at date of business combination, fair value														25,400,000
Income (Loss) from Continuing Operations Attributable to Noncontrolling Interest									(4,200,000)
Increase in contingent consideration	500,000
Noncontrolling interest	21,200,000								21,200,000
Research and Development Arrangement | Alios BioPharma, Inc
Collaborative revenues:
Intangible asset impairment charges					250,600,000
Change in deferred income taxes					102,100,000
Deconsolidation, Gain (Loss), Amount										68,200,000
Upfront license fees and milestone payments										120,000,000
Variable Interest Entity, Primary Beneficiary | BioAxone Biosciences, Inc
Noncontrolling Interest (Alios)
In-process research and development intangible asset	29,000,000								29,000,000
Deferred tax liability	11,300,000								11,300,000
Cash and cash equivalents	$ 8,400,000								$ 8,400,000