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Summary of Significant Accounting Policies (Details Textual)	1 Months Ended	12 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2018 USD ($) shares	Sep. 30, 2017 USD ($) shares	Sep. 30, 2018 GBP (£)
Significant Accounting Policies [Line Items]
Research and Development Expense		$ 823,000	$ 903,000
Cash, FDIC Insured Amount	$ 250,000	250,000
Operating Costs and Expenses		14,892,000	14,420,000
Other Research and Development Expense	35,000
Patent Costs		400,000	300,000
Advertising Expense		$ 145,000	$ 135,000
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares		160,537	196,769
Cash, Uninsured Amount	$ 2,000,000	$ 2,000,000	$ 1,900,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		24.28%	34.00%
Asset Impairment Charges		$ 182,000	$ 0
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount		700,000
Shipping and Handling [Member]
Significant Accounting Policies [Line Items]
Operating Costs and Expenses		40,000	45,000
Radiation Monitoring Devices Inc [Member]
Significant Accounting Policies [Line Items]
Research and Development Expense		9,900,000	10,700,000
Other Research and Development Expense		$ 800,000	900,000
Xcede Technologies inc [Member]
Significant Accounting Policies [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	63.00%	63.00%		63.00%
Finite-Lived Patents, Gross	$ 0	$ 0	100,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		21.00%
Asset Impairment Charges		$ 200,000
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%		17.00%
Dynasil Biomedical [Member]
Significant Accounting Policies [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	83.00%	83.00%		83.00%
Geographic Concentration Risk [Member] \| Accounts Receivable [Member]
Significant Accounting Policies [Line Items]
Accounts Receivable, Net	$ 1,724,000	$ 1,724,000	$ 863,000
Concentration Risk, Percentage		40.00%	25.00%
Maximum [Member] \| Acquired Customer Based [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life		20 years	20 years
Minimum [Member] \| Acquired Customer Based [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life		5 years	5 years
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
Hilger Crystals Ltd [Member]
Significant Accounting Policies [Line Items]
Cash, FDIC Insured Amount \| £				£ 75,000