Goodwill (Details) - USD ($)	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 5,940,000	$ 5,898,000
Currency translation on Hilger Crystals	(40,000)	42,000
Goodwill, Ending Balance	5,900,000	5,940,000
Contracts Research [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	4,939,000	4,939,000
Currency translation on Hilger Crystals	0	0
Goodwill, Ending Balance	4,939,000	4,939,000
Optics [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	1,001,000	959,000
Currency translation on Hilger Crystals	(40,000)	42,000
Goodwill, Ending Balance	$ 961,000	$ 1,001,000

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
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