Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($)	6 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Nov. 30, 2018	Sep. 30, 2018
Goodwill And Other Intangible Assets [Line Items]
Goodwill	$ 5,059,000			$ 4,343,000
Amortization expense	795,000	$ 0
Optoseis Technology
Goodwill And Other Intangible Assets [Line Items]
Goodwill	5,059,000		$ 700,000	4,343,000
Other intangible assets	$ 11,919,000		$ 3,700,000	$ 8,200,000

Goodwill and other intangible assets.

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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