Intangible Assets (Schedule Of Changes In The Carrying Amount Of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Arresto Biosciences, Inc. [Member]	Jan. 14, 2011 Arresto Biosciences, Inc. [Member]	Dec. 31, 2011 Calistoga Pharmaceuticals, Inc. [Member]	Apr. 02, 2011 Calistoga Pharmaceuticals, Inc. [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Balance at December 31, 2010	$ 1,004,102	$ 532,669
Goodwill resulting from acquisition			134,482	134,482	336,951	336,951
Balance at December 31, 2011	$ 1,004,102	$ 532,669