Revenue - Summary of Revenues Disaggregated by Product Classification and Operating Segment (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Disaggregation Of Revenue [Line Items]
Total revenue	$ 30,816	$ 24,344	$ 22,676	$ 22,241	$ 23,038	$ 22,227	$ 19,058	$ 17,013	$ 100,077	$ 81,336	$ 73,112
Product Sales [Member]
Disaggregation Of Revenue [Line Items]
Total revenue									40,219	37,953	32,790
Royalties [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		$ 1,000							48,458	35,424	31,787
Research, Development and Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenue									11,400	7,959	8,535
Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Total revenue									100,077	81,336	73,112
Operating Segments [Member] | Medical Device [Member]
Disaggregation Of Revenue [Line Items]
Total revenue									78,353	60,513	53,983
Operating Segments [Member] | Medical Device [Member] | Product Sales [Member]
Disaggregation Of Revenue [Line Items]
Total revenue									18,617	17,200	13,735
Operating Segments [Member] | Medical Device [Member] | Royalties [Member]
Disaggregation Of Revenue [Line Items]
Total revenue									34,781	30,606	30,264
Operating Segments [Member] | Medical Device [Member] | Research, Development and Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenue									11,277	7,889	8,528
Operating Segments [Member] | Medical Device [Member] | License Fees [Member]
Disaggregation Of Revenue [Line Items]
Total revenue									13,678	4,818	1,456
Operating Segments [Member] | In Vitro Diagnostics [Member]
Disaggregation Of Revenue [Line Items]
Total revenue									21,724	20,823	19,129
Operating Segments [Member] | In Vitro Diagnostics [Member] | Product Sales [Member]
Disaggregation Of Revenue [Line Items]
Total revenue									21,390	20,789	19,055
Operating Segments [Member] | In Vitro Diagnostics [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenue									$ 334	$ 34	$ 74