Goodwill and Other Intangible Assets - Schedule of Goodwill and Other Intangible Assets (Details) - USD ($)	12 Months Ended
	Sep. 30, 2018	Jul. 31, 2018	Sep. 30, 2017	Sep. 30, 2016
Goodwill And Other Intangible Assets [Line Items]
Goodwill	$ 4,343,000
Total other intangible assets			$ 0	$ 0
Other intangible assets, net	8,006,000
Quantum
Goodwill And Other Intangible Assets [Line Items]
Goodwill	4,343,000	$ 4,300,000
Total other intangible assets	8,200,000	$ 8,200,000
Accumulated amortization	(194,000)
Other intangible assets, net	$ 8,006,000
Weighted-Average Remaining Useful Lives (in years)	11 years 3 months 18 days
Quantum | Developed Technology
Goodwill And Other Intangible Assets [Line Items]
Total other intangible assets	$ 4,200,000
Weighted-Average Remaining Useful Lives (in years)	17 years 9 months 18 days
Quantum | Customer Relationships
Goodwill And Other Intangible Assets [Line Items]
Total other intangible assets	$ 2,500,000
Weighted-Average Remaining Useful Lives (in years)	4 years 9 months 18 days
Quantum | Trade Names
Goodwill And Other Intangible Assets [Line Items]
Total other intangible assets	$ 1,400,000
Weighted-Average Remaining Useful Lives (in years)	3 years 9 months 18 days
Quantum | Non-compete Agreements
Goodwill And Other Intangible Assets [Line Items]
Total other intangible assets	$ 100,000
Weighted-Average Remaining Useful Lives (in years)	3 years 9 months 18 days