Restructuring and Related Costs (Narrative) (Details)	3 Months Ended	6 Months Ended
Mar. 28, 2020 USD ($)	Mar. 28, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Payments for restructuring	$ 0
Test & Simulation
Restructuring Cost and Reserve [Line Items]
Restructuring charges	6,138,000	$ 6,138,000
Test & Simulation \| Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	7,000,000	7,000,000
Test & Simulation \| Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	$ 10,600,000	$ 10,600,000

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount expected to be recognized in earnings for the specified restructuring cost.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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