Summary of Significant Accounting Policies (Detail) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Non-cash changes in inventory	$ 294	$ 602
Research and Development Expense (in Dollars)	$ 2,362	$ 2,984
Number of Years Defined Benefit Plans are Closed to Newly Hired Employees	2 years
Number of Years Supplementary Retirement Plans are Closed to Newly Hired Employees	2 years
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in Shares)		25
Stock-based compensation expense on stock options and restricted stock awards	$ 577	$ 414
Minimum
Finite-Lived Intangible Asset, Useful Life	3 years
Property, Plant and Equipment, Useful Life	3 years
Hardware Warranty Included in Product Sales	90 days
Maximum
Finite-Lived Intangible Asset, Useful Life	10 years
Property, Plant and Equipment, Useful Life	7 years
Hardware Warranty Included in Product Sales	3 years
Systems Segment [Member]
Royalty revenue	$ 5,400	$ 4,300

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Number of years that all of the Company's defined benefit plans are closed to newly hired employees.

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Number of years that the Company's supplementary retirement plans are closed to newly hired employees.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Revenue earned during the period from the leasing or otherwise lending to a third party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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