Goodwill and Other Intangible Assets - Schedule of Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2019	Nov. 30, 2018	Sep. 30, 2018
Goodwill And Other Intangible Assets [Line Items]
Goodwill	$ 5,059		$ 4,343
Other intangible assets, net	10,930		8,006
Optoseis Technology
Goodwill And Other Intangible Assets [Line Items]
Goodwill	5,059	$ 700	4,343
Total other intangible assets	11,919	$ 3,700	8,200
Accumulated amortization	(989)		(194)
Other intangible assets, net	$ 10,930		8,006
Weighted-Average Remaining Useful Lives (in years)	10 years 6 months
Optoseis Technology | Developed Technology
Goodwill And Other Intangible Assets [Line Items]
Total other intangible assets	$ 5,919		4,200
Weighted-Average Remaining Useful Lives (in years)	17 years 4 months 24 days
Optoseis Technology | Customer Relationships
Goodwill And Other Intangible Assets [Line Items]
Total other intangible assets	$ 3,900		2,500
Weighted-Average Remaining Useful Lives (in years)	3 years 4 months 24 days
Optoseis Technology | Trade Names
Goodwill And Other Intangible Assets [Line Items]
Total other intangible assets	$ 1,930		1,400
Weighted-Average Remaining Useful Lives (in years)	4 years 6 months
Optoseis Technology | Non-compete Agreements
Goodwill And Other Intangible Assets [Line Items]
Total other intangible assets	$ 170		$ 100
Weighted-Average Remaining Useful Lives (in years)	3 years 6 months