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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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The quantified amount of the future effect on cash flows.

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The adjustment to reduce the value of existing agreements that specify the lessee's rights to use the leased property. This expense is charged when the estimates of future profits generated by the leased property are reduced.

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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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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Amount of loss from impairment of right-of-use asset from operating lease.

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

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- Definition

The number of positions eliminated during the period as a result of restructuring activities.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after cash payment, 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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Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

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RESTRUCTURING CHARGES - Narrative (Details) $ in Thousands			3 Months Ended				6 Months Ended
RESTRUCTURING CHARGES - Narrative (Details) $ in Thousands	Nov. 12, 2020 USD ($)	Sep. 30, 2020 USD ($) position	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2021 USD ($) position	Mar. 31, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 7,562			$ 3,104	$ 18,362	$ 9,538
Non-cash charges			2,497	$ 5,794
Consumer and Professional Products
Restructuring Cost and Reserve [Line Items]
Restructuring charges			7,502			3,104	10,581	9,538
Next-generation Business Platform \| Consumer and Professional Products
Restructuring Cost and Reserve [Line Items]
Restructuring costs							7,891	4,846
Non-cash charges							$ 2,690	4,692
Impairment charge, operating lease								1,968
Impairment charge, leasehold improvements								671
Inventory write down								304
Impairment charge, manufacturing assets								1,749
Reduction of headcount \| position							65
Voluntary Employee Retirement Plan \| Defense Electronics
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost		$ 4,300			$ 4,300
Restructuring charges					$ 2,120		$ 2,180
Reduction of headcount \| position		90
Exit of Older Weather Radar Product Lines
Restructuring Cost and Reserve [Line Items]
Business exit costs				5,601
Minimum \| Next-generation Business Platform \| Consumer and Professional Products
Restructuring Cost and Reserve [Line Items]
Annual cash savings	$ 30,000
Reduction in inventory	30,000
Maximum \| Next-generation Business Platform \| Consumer and Professional Products
Restructuring Cost and Reserve [Line Items]
Annual cash savings	35,000
Reduction in inventory	35,000
One-time charges \| Next-generation Business Platform \| Consumer and Professional Products
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	65,000
Capital investments \| Next-generation Business Platform \| Consumer and Professional Products
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	65,000
Cash charges \| Next-generation Business Platform \| Consumer and Professional Products
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	46,000
Personnel related costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges			782			1,658	3,264	3,792
Non-cash charges			0	0
Personnel related costs \| Next-generation Business Platform \| Consumer and Professional Products
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	26,000
Restructuring costs							1,084	3,792
Facilities, exit costs and other
Restructuring Cost and Reserve [Line Items]
Restructuring charges			4,283			$ 914	6,807	1,054
Non-cash charges			$ 0	$ 0
Facilities, exit costs and other \| Next-generation Business Platform \| Consumer and Professional Products
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	20,000
Restructuring costs							$ 6,807	$ 1,054
Asset write-downs \| Next-generation Business Platform \| Consumer and Professional Products
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	$ 19,000