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It describes the consolidated fixed charge coverage ratio.

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The imputed interest rate used to calculate the fair value of the note.

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Represent the invest amount in exchange for preferred stock.

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It represents the purchase price of debt which is classified under subordinate.

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Total current liabilities of the broker-dealer, less certain exceptions as defined.

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount of the required periodic payments including both interest and principal payments.

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Amount of the required periodic payments applied to principal.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt (Details Textual) - USD ($)	1 Months Ended		12 Months Ended
Debt (Details Textual) - USD ($)	Nov. 30, 2016	Jul. 31, 2012	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015	May 16, 2017	Dec. 02, 2016	Feb. 01, 2016	Sep. 29, 2015	May 01, 2014
Debt [Line Items]
Payment of Subordinate Debt					$ 2,000,000
Description Of Consolidated Fixed Charge Coverage Ratio			The Bank Loan Agreement requires Dynasil, at the close of each fiscal quarter, to maintain a Debt Service Coverage ratio, as defined, of at least 1.20 to 1.00 on a trailing four quarter basis.
Amortization of Debt Issuance Costs			$ 3,000	$ 9,000
Debt Issuance Costs, Net			64,000	64,000
Accumulated Amortization, Debt Issuance Costs			$ 64,000	$ 61,000
Notes Payable To Banks Member [Member]
Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis			(i) a security interest in substantially all of the Company’s personal property and (ii) sixty-five percent (65%) of Dynasil’s equity interests in its U.K. subsidiary, Hilger Crystals, Ltd. Under the Note, the borrowing base is determined monthly based on eligible billed and unbilled accounts receivable and eligible inventory. The interest rate under the Note is equal to the Prime Rate, but in no event less than 3.25%.
Masschusetts Capital Resource Corporation [Member]
Debt [Line Items]
Debt Instrument, Face Amount		$ 3,000,000							$ 3,000,000
Masschusetts Capital Resource Corporation [Member] \| 6.00% Note Payable [Member]
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.00%
Debt Instrument, Periodic Payment, Principal			$ 43,478		$ 130,000
Debt Instrument, Maturity Date, Description			July 31, 2019
Middlesex Savings Bank [Member]
Debt [Line Items]
Debt Instrument, Maturity Date			May 01, 2017
Debt Instrument, Interest Rate, Stated Percentage			4.52%					4.50%
Long-term Line of Credit								$ 1,400,000
Line of Credit, Current			$ 4,000,000					2,000,000		$ 4,000,000
Middlesex Savings Bank [Member] \| 4.52% Term Note Payable [Member]
Debt [Line Items]
Debt Instrument, Maturity Date			Feb. 01, 2021
Debt Instrument, Periodic Payment			$ 37,000
Short-term Debt								$ 2,000,000
Town of Ayer Industrial Development Finance Authority [Member]
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.00%
Debt Instrument, Periodic Payment, Principal			$ 17,000
Massachusetts Development Finance Agency [Member]
Debt [Line Items]
Debt Instrument, Maturity Date			Mar. 01, 2019
Debt Instrument, Interest Rate, Stated Percentage			5.25%
Debt Instrument, Periodic Payment			$ 6,000
Optometrics Corporation [Member] \| Maximum [Member]
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.25%
Optometrics Corporation [Member] \| Minimum [Member]
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.00%
Radiation Monitoring Devices, Inc [Member] \| Maximum [Member]
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			14.59%
Radiation Monitoring Devices, Inc [Member] \| Minimum [Member]
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			8.70%
Leaf Capital Funding, LLC [Member] \| 14.59% Note Payable [Member]
Debt [Line Items]
Debt Instrument, Maturity Date			Feb. 28, 2018
Debt Instrument, Interest Rate, Stated Percentage			14.59%
Debt Instrument, Periodic Payment			$ 7,000
Leaf Capital Funding, LLC [Member] \| 8.70% Note Payable [Member]
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			8.70%
Debt Instrument, Periodic Payment			$ 1,000
Note Purchase Agreement [Member]
Debt [Line Items]
Payment of Subordinate Debt		$ 3,000,000
Debt Instrument, Interest Rate, Stated Percentage			10.00%
Xcede Technologies inc [Member]
Debt [Line Items]
Proceeds from Convertible Debt			$ 2,900,000
Debt Instrument, Maturity Date			Jun. 30, 2017
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,500,000
Debt Instrument, Interest Rate, Stated Percentage	2.00%		5.00%
Debt Instrument, Face Amount			$ 2,200,000
Aggregate Indebtedness			$ 500,000
Equity Method Investment, Ownership Percentage			61.00%
Debt Conversion, Converted Instrument, Shares Issued	5,394,120
Capital Stock Financing Discount Percentage	20.00%
Imputed Interest Rate			5.40%
Proceeds from Lines of Credit	$ 500,000
Xcede Note agreement with Cook Biotech Inc [Member]
Debt [Line Items]
Debt Instrument, Face Amount			$ 500,000
Equipment Line Of Credit [Member] \| Middlesex Savings Bank [Member]
Debt [Line Items]
Line of Credit, Current						$ 1,000,000
Senior Debt [Member] \| Xcede Technologies inc [Member]
Debt [Line Items]
Invest Amount In Exchange For Preferred Stock							$ 1,200,000