Marketable Securities (Details 2) (USD $)	Dec. 31, 2013		Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Cash equivalents (Alios)	$ 0	[1]	$ 69,983,000	[1]
Alios BioPharma, Inc
Schedule of Available-for-sale Securities [Line Items]
Cash equivalents (Alios)			70,000,000	[1]
Foreign currency forward contract
Schedule of Available-for-sale Securities [Line Items]
Derivative, Notional Amount	$ 17,500,000

[1] Amounts as of December 31, 2012 include the assets and liabilities of Vertex’s variable interest entity (“VIE”), Alios BioPharma, Inc. (“Alios”). The Company deconsolidated Alios as of December 31, 2013. 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 B, "Collaborative Arrangements," to these consolidated financial statements for amounts.