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Recent Accounting Pronouncements - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Oct. 01, 2018
Deferred Revenue, Revenue Recognized	$ 0	$ 253,000
Impact of Restatement on Opening Retained Earnings, Net of Tax					$ 22,000
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	$ 38,300,000	38,300,000
Optics [Member]
Revenue, Remaining Performance Obligation, Amount	$ 7,000,000	$ 7,000,000
Scenario, Forecast [Member] \| Innovation and Development Segment [Member]
Revenue, Remaining Performance Obligation, Percentage			55.00%	34.00%
Scenario, Forecast [Member] \| Optics [Member]
Revenue, Remaining Performance Obligation, Percentage			47.00%	53.00%