Reportable Segments and Major Concentration Data - Significant Revenue Information by Country for Diagnostics and Life Science Reportable Segments (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 53,100	$ 51,737	$ 56,451	$ 52,283	$ 49,697	$ 50,140	$ 54,125	$ 46,809	$ 213,571	$ 200,771	$ 196,082
Diagnostics [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									150,454	143,521	145,114
Diagnostics [Member] | United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									125,959	119,332	122,264
Diagnostics [Member] | Italy [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									7,648	6,601	6,717
Diagnostics [Member] | France [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									2,363	1,856	1,619
Diagnostics [Member] | United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									2,337	1,789	2,018
Diagnostics [Member] | Belgium [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									1,719	1,517	1,471
Diagnostics [Member] | Holland [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									1,460	1,297	1,215
Diagnostics [Member] | Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									1,263	2,209	1,665
Diagnostics [Member] | Other Countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									7,705	8,920	8,145
Life Science [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									63,117	57,250	50,968
Life Science [Member] | United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									20,442	19,627	19,212
Life Science [Member] | France [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									2,037	1,791	1,054
Life Science [Member] | United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									5,190	5,574	5,581
Life Science [Member] | Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									1,928	1,374	1,542
Life Science [Member] | Other Countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									7,157	6,080	5,380
Life Science [Member] | China [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									8,329	5,893	4,077
Life Science [Member] | Germany [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									8,198	7,400	6,999
Life Science [Member] | Spain [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									4,179	3,206	2,917
Life Science [Member] | Australia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									3,617	3,999	3,163
Life Science [Member] | South Korea [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									$ 2,040	$ 2,306	$ 1,043