Goodwill (Details) (USD $) In Thousands					3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2011		Dec. 31, 2010		Mar. 31, 2011 Lead Therapeutics, Inc. [Member]	Sep. 30, 2011 Lead Therapeutics, Inc. [Member]	Sep. 30, 2011 ZyStor Therapeutics, Inc. [Member]	Sep. 30, 2011 ZyStor Therapeutics, Inc. [Member]
Goodwill [Line Items]
Balance at December 31, 2010	$ 51,543		$ 53,364	[1]
Reduction of goodwill related to acquisition					300	309	1,500	1,512
Balance at September 30, 2011	51,543		53,364	[1]
Retention of a portion of acquisition consideration withheld	$ 38,020	[2]	$ 43,718	[2]			$ 2,000	$ 2,000

[1] December 31, 2010 balances were derived from the audited consolidated financial statements.

[2] At September 30, 2011 and December 31, 2010, 86% and 80%, respectively, of the contingent acquisition consideration payable was included in other long-term liabilities and 14% and 20%, respectively, was included in accounts payable and accrued liabilities.