Significant Transactions - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended				3 Months Ended		9 Months Ended			9 Months Ended			3 Months Ended	9 Months Ended				3 Months Ended	9 Months Ended	1 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	May 31, 2013	Dec. 31, 2012	Sep. 30, 2013 CMIC Co., Ltd, (CMIC)	Sep. 30, 2012 CMIC Co., Ltd, (CMIC)	Sep. 30, 2013 CMIC Co., Ltd, (CMIC)	Sep. 30, 2012 CMIC Co., Ltd, (CMIC)	Dec. 31, 2012 CMIC Co., Ltd, (CMIC)	Sep. 30, 2013 CMIC Co., Ltd, (CMIC) Maximum	Sep. 30, 2013 CMIC Co., Ltd, (CMIC) Minimum	Sep. 30, 2013 CMIC Co., Ltd, (CMIC) Up-front Payment Arrangement	Sep. 30, 2012 Sigma Tau	Sep. 30, 2013 Sigma Tau	Sep. 30, 2012 Sigma Tau	Sep. 30, 2013 Sigma Tau Contract Termination	Sep. 30, 2013 Sigma Tau Development Services	Sep. 30, 2013 CVie Therapeutics	Sep. 30, 2013 CVie Therapeutics	Feb. 28, 2013 CVie Therapeutics Up-front Payment Arrangement	Feb. 28, 2013 CVie Therapeutics Up-front Payment Arrangement Maximum	Sep. 30, 2013 Novellus Plan	Sep. 30, 2013 Novellus Plan Up-front Payment Arrangement	Sep. 30, 2013 Novellus Plan Up-front Payment Arrangement Maximum
Significant Transactions [Line Items]
Collaboration arrangement payment														$ 4,000,000					$ 7,000,000			$ 1,000,000			$ 500,000
Proceed from development and sales milestones												102,000,000												800,000
Percentage of revenue to receive from development and sales milestones												24.00%	20.00%
Revenue	13,691,000	13,101,000	37,067,000	38,620,000			192,000	189,000	589,000	566,000										47,000	125,000
Deferred revenue							2,000,000		2,000,000		2,500,000									875,000	875,000			800,000
Collaboration arrangement receivable																							11,000,000			5,200,000
Reimbursement from collaboration arrangement																			3,800,000
Common stock purchase price	110,347,285		110,347,285		8,901,675	98,798,065												271,665	787,647
Common stock aggregate purchase price																			3,000,000
Consideration contractually obligated to pay contingent upon future sales																		500,000
Compensation received during the next ten years in relation to the license or supply of ecallantide																		5,000,000
Reduction to development and license fee revenue																1,100,000
Deferred revenue, revenue recognized															$ 69,000	$ 85,000	$ 156,000