Summary of Significant Accounting Policies and Select Balance Sheet Information - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Intangible Assets [Line Items]
Definite-lived intangible assets, Accumulated Amortization	$ (18,746)	$ (15,769)
Intangible assets, Gross Carrying Amount	32,029	29,995
Intangible assets, Net	$ 13,283	$ 14,226
Customer Lists and Relationships [Member]
Intangible Assets [Line Items]
Definite-lived intangible assets, Weighted Average Original Life (Years)	8 years 10 months 24 days	8 years 10 months 24 days
Definite-lived intangible assets, Gross Carrying Amount	$ 18,213	$ 17,374
Definite-lived intangible assets, Accumulated Amortization	(12,451)	(10,661)
Definite-lived intangible assets, Net	$ 5,762	$ 6,713
Developed Technology [Member]
Intangible Assets [Line Items]
Definite-lived intangible assets, Weighted Average Original Life (Years)	11 years 6 months	11 years 6 months
Definite-lived intangible assets, Gross Carrying Amount	$ 9,685	$ 9,490
Definite-lived intangible assets, Accumulated Amortization	(4,200)	(3,196)
Definite-lived intangible assets, Net	$ 5,485	$ 6,294
Non-compete [Member]
Intangible Assets [Line Items]
Definite-lived intangible assets, Weighted Average Original Life (Years)	5 years	5 years
Definite-lived intangible assets, Gross Carrying Amount	$ 230	$ 230
Definite-lived intangible assets, Accumulated Amortization	$ (230)	(196)
Definite-lived intangible assets, Net		$ 34
Patents and Other [Member]
Intangible Assets [Line Items]
Definite-lived intangible assets, Weighted Average Original Life (Years)	14 years 8 months 12 days	16 years 6 months
Definite-lived intangible assets, Gross Carrying Amount	$ 3,321	$ 2,321
Definite-lived intangible assets, Accumulated Amortization	(1,865)	(1,716)
Definite-lived intangible assets, Net	1,456	605
Definite-Lived Intangible Assets [Member]
Intangible Assets [Line Items]
Definite-lived intangible assets, Gross Carrying Amount	31,449	29,415
Definite-lived intangible assets, Accumulated Amortization	(18,746)	(15,769)
Definite-lived intangible assets, Net	12,703	13,646
Trademarks and Trade Names [Member]
Intangible Assets [Line Items]
Indefinite-lived intangible assets, Net	$ 580	$ 580