Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Revenue:
Research, development and other	$ 2,394	$ 1,849
Total revenue	$ 22,241	$ 17,013
Operating costs and expenses:
Type of Cost, Good or Service [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember
Product costs	$ 3,523	$ 2,891
Research and development	11,486	7,831
Selling, general and administrative	5,949	5,188
Acquired intangible asset amortization	606	618
Contingent consideration (gain) expense	(35)	1,118
Total operating costs and expenses	21,529	17,646
Operating income (loss)	712	(633)
Other income:
Investment income, net	316	121
Interest expense	(37)
Foreign exchange gain (loss)	136	(186)
Gain on strategic investment and other	7	177
Other income, net	422	112
Income (loss) before income taxes	1,134	(521)
Income tax provision	176	(1,035)
Net income (loss)	$ 1,310	$ (1,556)
Basic net income (loss) per share	$ 0.10	$ (0.12)
Diluted net income (loss) per share	$ 0.09	$ (0.12)
Weighted average number of shares outstanding:
Basic	13,367	13,064
Diluted	13,827	13,064
Product Sales [Member]
Revenue:
Revenue	$ 9,751	$ 8,088
Royalties and License Fees [Member]
Revenue:
Revenue	$ 10,096	$ 7,076