Significant Accounting Policies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended			3 Months Ended							12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 Rapiacta [Member]	Sep. 30, 2012 Rapiacta [Member]	Dec. 31, 2013 Money Market Funds [Member]	Dec. 31, 2012 Money Market Funds [Member]	Dec. 31, 2013 Royalty Receivable [Member] Shionogi & Co. Ltd [Member]	Dec. 31, 2012 Royalty Receivable [Member] Shionogi & Co. Ltd [Member]	Mar. 09, 2011 JPR Royalty Sub LLC [Member]	Dec. 31, 2013 Laboratory Equipment [Member]	Dec. 31, 2013 Office Equipment [Member]	Dec. 31, 2013 Furniture and Fixtures [Member]	Dec. 31, 2013 Software [Member]	Dec. 31, 2013 Maximum [Member]	Dec. 31, 2013 Minimum [Member]
Significant Accounting Policies [Line Items]
Cash and Investments		$ 40,788
Proceeds from non-recourse notes										30,000
Maturity of investments															3 months
Restricted cash	151	308				150	300	1	8
Maturity period for high-quality marketable securities															3 years
Average portfolio maturity period for high-quality marketable securities															18 months
Maturity period of investments															12 months	3 months
Maturity period of longterm investments	12 months
Estimated useful lives											5 years	5 years	7 years	5 years	7 years	5 years
Property plant and equipment depreciation methods description	Depreciation is computed using the straight-line method with estimated useful lives of five and seven years.
Leasehold improvement amortization description	Leasehold improvements are amortized over their estimated useful lives or the remaining lease term, whichever is less.
Accrued expenses	2,210	6,573
Royalty revenue recognized	2,562	3,317		469	2,848
Interest expenses	4,778	4,666	3,774
Amortization of deferred financing costs	439	439	356
Cumulative mark-to-market adjustments - loss	5,294	(749)	(4,000)
Hedge collateral under the agreement	$ 0	$ 5,180
Antidilutive effect of shares issued under employee Stock Purchase Plan	2,109	1,026	1,003
Average maturity for portfolio investments															24 months