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Summary of Significant Accounting Policies (Details Textual)	12 Months Ended
	Sep. 30, 2017 USD ($) shares	Sep. 30, 2016 USD ($) shares	Sep. 30, 2017 GBP (£)
Significant Accounting Policies [Line Items]
Patent costs	$ 300,000	$ 200,000
Advertising Expense	117,000	105,000
Cash, FDIC Insured Amount	250,000
Cash, Uninsured Amount	1,930,000	2,031,000
Accrual For Contract Losses	$ 110,000	$ 110,000
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares	196,769	123,147
Shipping and Handling Revenue	$ 45,000	$ 49,000
Research and Development Expense, Total	903,000	998,000
Other Research and Development Expense	900,000	1,000,000
Income Tax Expense (Benefit)	$ (2,741,000)	51,000
Hilger Crystals, Ltd [Member]
Significant Accounting Policies [Line Items]
Cash, FDIC Insured Amount \| £			£ 75,000
Transportation Equipment [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Building and Building Improvements [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	25 years
Building and Building Improvements [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	8 years
Machinery and Equipment [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	20 years
Machinery and Equipment [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Furniture and Fixtures [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Furniture and Fixtures [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Geographic Concentration Risk [Member] \| Accounts Receivable [Member]
Significant Accounting Policies [Line Items]
Accounts Receivable, Net, Total	$ 863,000	$ 1,159,000
Concentration Risk, Percentage	25.00%	32.00%
Acquired Customer Base [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years	15 years
Acquired Customer Base [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years	5 years
Radiation Monitoring Devices, Inc [Member]
Significant Accounting Policies [Line Items]
Research and Development Expense, Total	$ 10,700,000	$ 12,200,000
Xcede Technologies inc [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Patents, Gross	$ 100,000	$ 100,000
Noncontrolling Interest, Ownership Percentage by Parent	61.00%		61.00%
Income Tax Expense (Benefit)	$ (2,700,000)
Xcede Technologies inc [Member] \| Common Stock Owned By Others [Member]
Significant Accounting Policies [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	17.00%		17.00%
Dynasil Biomedical [Member]
Significant Accounting Policies [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	83.00%		83.00%