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Recent Accounting Pronouncements (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
	Mar. 31, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Oct. 01, 2018
Contract with Customer, Liability, Revenue Recognized	$ 137,000	$ 252,000
Revenue, Performance Obligation, Description of Payment Terms	cost-plus contracts, the customer generally pays during the performance period for 80%-90% of the actual costs incurred.
Innovation and Development Segment [Member]
Revenue, Remaining Performance Obligation, Amount	$ 32,800,000	32,800,000
Optics [Member]
Revenue, Remaining Performance Obligation, Amount	$ 3,200,000	$ 3,200,000
Scenario, Forecast [Member] \| Innovation and Development Segment [Member]
Revenue, Remaining Performance Obligation, Percentage			41.00%	46.00%
Scenario, Forecast [Member] \| Optics [Member]
Revenue, Remaining Performance Obligation, Percentage			14.00%	86.00%
Retained Earnings [Member]
Impact of Restatement on Opening Retained Earnings, Net of Tax					$ 22,000