Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue:
Total revenue	$ 24,344	$ 22,227	$ 69,261	$ 58,298
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	$ 3,364	$ 4,104	$ 9,980	$ 9,908
Research and development	13,321	9,778	38,362	28,383
Selling, general and administrative	5,939	5,977	16,764	17,606
Acquired in-process research and development		7,888		7,888
Acquired intangible asset amortization	599	624	1,809	1,878
Contingent consideration expense (gain)	104	106	(248)	(1,006)
Total operating costs and expenses	23,327	28,477	66,667	64,657
Operating income (loss)	1,017	(6,250)	2,594	(6,359)
Other income (loss):
Investment income, net	269	303	850	566
Interest expense	(38)		(112)
Foreign exchange (loss) gain	(42)	652	99	113
Gain on strategic investment and other			9	177
Other income, net	189	955	846	856
Income (loss) before income taxes	1,206	(5,295)	3,440	(5,503)
Income tax benefit	260	2,613	598	2,799
Net income (loss)	$ 1,466	$ (2,682)	$ 4,038	$ (2,704)
Basic net income (loss) per share	$ 0.11	$ (0.20)	$ 0.30	$ (0.21)
Diluted net income (loss) per share	$ 0.11	$ (0.20)	$ 0.29	$ (0.21)
Weighted average number of shares outstanding:
Basic	13,394	13,203	13,384	13,117
Diluted	13,726	13,203	13,776	13,117
Product Sales [Member]
Revenue:
Total revenue	$ 9,870	$ 10,475	$ 29,508	$ 27,249
Royalties and License Fees [Member]
Revenue:
Total revenue	11,624	9,597	31,652	25,101
Research, Development and Other [Member]
Revenue:
Total revenue	$ 2,850	$ 2,155	$ 8,101	$ 5,948