Acquisition of ViroChem Pharma Inc. (Details) (USD $)	3 Months Ended		9 Months Ended			1 Months Ended	9 Months Ended					9 Months Ended
	Sep. 30, 2011		Sep. 30, 2011		Dec. 31, 2010	Mar. 31, 2009 ViroChem stages	Sep. 30, 2011 ViroChem	Dec. 31, 2010 ViroChem	Mar. 12, 2009 ViroChem	Sep. 30, 2011 ViroChem VX-222	Dec. 31, 2010 ViroChem VX-222	Sep. 30, 2011 ViroChem VX-759	Jun. 30, 2011 ViroChem VX-759	Dec. 31, 2010 ViroChem VX-759
Business Acquisition
Percent of voting interest acquired in ViroChem (as a percent)									100.00%
Number of clinical-development stage HCV drugs added to drug development portfolio (in stages)						2
Portion of purchase price paid in common shares for the acquisition of ViroChem (in shares)						10,733,527
Acquisition-date fair value of the consideration
Cash									$ 100,000,000
Intangible assets	663,500,000	[1]	663,500,000	[1]	518,700,000					412,900,000	412,900,000		105,800,000	105,800,000
Fair value at date of acquisition												0
Intangible asset impairment charge	105,800,000		105,800,000									105,800,000
Deferred tax liability adjustment associated with impairment recognition							(32,700,000)
Deferred tax liability	$ 231,184,000	[1]	$ 231,184,000	[1]	$ 160,278,000		$ 127,600,000	$ 160,300,000

[1] Amounts include the assets and liabilities of Vertex's variable interest entity ("VIE"), Alios BioPharma, Inc. ("Alios"). Vertex's interests and obligations with respect to the VIE's assets and liabilities are limited to those accorded to Vertex in its agreement with Alios. See Note K to these condensed consolidated financial statements for amounts.