Significant Accounting Policies - Summary of Disaggregation of Revenue by Product Platform/Type (Detail) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Revenue	$ 51,480	$ 52,283
Revenue, % change	(2.00%)
Diagnostics [Member]
Segment Reporting Information [Line Items]
Revenue	$ 36,665	37,490
Revenue, % change	(2.00%)
Diagnostics [Member] | Molecular Assays [Member]
Segment Reporting Information [Line Items]
Revenue	$ 7,298	8,717
Revenue, % change	(16.00%)
Diagnostics [Member] | Immunoassays & Blood Chemistry Assays [Member]
Segment Reporting Information [Line Items]
Revenue	$ 29,367	28,773
Revenue, % change	2.00%
Life Science [Member]
Segment Reporting Information [Line Items]
Revenue	$ 14,815	14,793
Life Science [Member] | Molecular Reagents [Member]
Segment Reporting Information [Line Items]
Revenue	$ 6,589	5,688
Revenue, % change	16.00%
Life Science [Member] | Immunological Reagents [Member]
Segment Reporting Information [Line Items]
Revenue	$ 8,226	$ 9,105
Revenue, % change	(10.00%)