Marketable Securities (Details 2) (USD $) In Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010	Sep. 30, 2011		Sep. 30, 2010
Marketable Securities
Cash equivalents (Alios)	$ 50,580	[1]		$ 50,580	[1]
Proceeds from sales and maturities of marketable securities:
Sales and maturities of marketable securities	$ 135,100		$ 461,700	$ 923,123		$ 979,791

[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.