Acquisitions, License and Research Agreements (Details 2) (Meritage Pharma, Inc., USD $) In Millions, unless otherwise specified	1 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended
	Jul. 31, 2013	Dec. 31, 2011	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2011
Maximum
License and research agreements disclosures
Business development agreement, potential cash payment			$ 5.0		$ 5.0
Cost-method investment
License and research agreements disclosures
Payment to purchase interest in development company	2.5	7.5		5.0
Percentage of subjects planned for the Phase 2 study enrollment	50.00%
Number of business days used to determine period for providing written notice							30 days
Agreed upon purchase price of the outstanding stock per optional purchase agreement		69.9					69.9
Maximum contingent consideration, potential cash payment		175					175
Amortization expense			$ 1.4	$ 1.1	$ 3.5	$ 2.7