Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Revenue:
Research, development and other	$ 7,959	$ 8,535	$ 7,164
Total revenue	$ 81,336	$ 73,112	$ 71,366
Operating costs and expenses:
Type of Cost, Good or Service [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Product costs	$ 13,997	$ 11,422	$ 10,908
Research and development	40,973	31,817	18,498
Selling, general and administrative	24,111	20,478	18,000
Acquired in-process research and development	7,888
Acquired intangible asset amortization	2,491	2,419	2,422
Contingent consideration expense (gain)	675	(127)	1,492
Acquisition transaction, integration and other costs			3,187
Total operating costs and expenses	90,135	66,009	54,507
Operating (loss) income	(8,799)	7,103	16,859
Other income (loss):
Investment income, net	851	390	63
Foreign exchange gain (loss)	239	(504)	(481)
Gains on strategic investments and other	177	44	507
Other income (loss)	1,267	(70)	89
(Loss) income before income taxes	(7,532)	7,033	16,948
Income tax benefit (provision)	3,075	(3,107)	(6,963)
Net (loss) income	$ (4,457)	$ 3,926	$ 9,985
Basic net (loss) income per share:	$ (0.34)	$ 0.30	$ 0.77
Diluted net (loss) income per share:	$ (0.34)	$ 0.29	$ 0.76
Weighted average number of shares outstanding:
Basic	13,157	13,153	12,998
Diluted	13,157	13,389	13,219
Product Sales [Member]
Revenue:
Revenue	$ 37,953	$ 32,790	$ 30,999
Royalties and License Fees [Member]
Revenue:
Revenue	$ 35,424	$ 31,787	$ 33,203