Segment Data and Related Information (Schedule of Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Revenue	$ 25,482	$ 24,001
Gross profit	7,474	5,808
R&D expense	4,642	4,019
Operating loss	(1,453)	(5,804)
Unallocated (income) expense:
Selling, general, and administrative	5,887	7,593
Gain on sale of assets	(1,602)	0
Interest (expense) income, net	15	(267)
Foreign exchange gain	(147)	(14)
Total unallocated expense	4,153	7,312
Loss before income tax expense	(1,321)	(5,523)
Operating segments
Segment Reporting Information [Line Items]
Revenue	25,482	24,001
Operating loss	2,832	1,789
Operating segments \| Aerospace And Defense
Segment Reporting Information [Line Items]
Revenue	13,704	4,140
Gross profit	4,488	1,222
R&D expense	3,951	1,551
Operating loss	537	(329)
Operating segments \| Broadband
Segment Reporting Information [Line Items]
Revenue	11,778	19,861
Gross profit	2,986	4,586
R&D expense	691	2,468
Operating loss	$ 2,295	$ 2,118

The amount of unallocated income (expense) which was not separately allocated to segments.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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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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