Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue:
Research, development and other	$ 2,155	$ 2,219	$ 5,948	$ 6,526
Total revenue	$ 22,227	$ 17,790	$ 58,298	$ 53,054
Operating costs and expenses:
Type of Cost, Good or Service [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Product costs	$ 4,104	$ 2,914	$ 9,908	$ 8,104
Research and development	9,778	7,927	28,383	22,105
Selling, general and administrative	5,977	5,232	17,606	15,170
Acquired in-process research and development	7,888		7,888
Acquired intangible asset amortization	624	603	1,878	1,790
Contingent consideration expense (gain)	106	(629)	(1,006)	(803)
Total operating costs and expenses	28,477	16,047	64,657	46,366
Operating (loss) income	(6,250)	1,743	(6,359)	6,688
Other income (loss):
Investment income, net	303	104	566	274
Foreign exchange gain (loss)	652	(594)	113	(121)
Gain on strategic investment			177
Other income (loss), net	955	(490)	856	153
(Loss) income before income taxes	(5,295)	1,253	(5,503)	6,841
Income tax benefit (provision)	2,613	(533)	2,799	(3,315)
Net (loss) income	$ (2,682)	$ 720	$ (2,704)	$ 3,526
Basic net (loss) income per share	$ (0.20)	$ 0.05	$ (0.21)	$ 0.27
Diluted net (loss) income per share	$ (0.20)	$ 0.05	$ (0.21)	$ 0.26
Weighted average number of shares outstanding:
Basic	13,203	13,155	13,117	13,190
Diluted	13,203	13,385	13,117	13,404
Product sales [Member]
Revenue:
Revenue	$ 10,475	$ 8,327	$ 27,249	$ 23,964
Royalties and License Fees [Member]
Revenue:
Revenue	$ 9,597	$ 7,244	$ 25,101	$ 22,564