Represents carrying value of the assets set aside to fund potential deferred compensation liabilities.

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Represents costs incurred outside the scope of work on several contacts or in advance of a contract award included in work in process and inventoried costs under long-term contracts.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

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No definition available.

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Actual or estimated amount of general and administrative costs remaining in inventory.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of items purchased for use as components of a finished product or pieces of machinery and equipment plus any items in their natural and unrefined state. This element may be used when the reporting entity combines raw materials and purchased parts into an aggregate amount.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Balance Sheet Details (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Balance Sheet Details (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2020	Sep. 30, 2019
Restricted Cash
Restricted cash			$ 23,900	$ 29,500
Inventories
Finished products			16,825	10,905
Work in process and inventoried costs under long-term contracts			90,731	46,951
Materials and purchased parts			44,057	48,938
Net inventories			151,613	106,794
Costs incurred outside the scope of work or in advance of a contract award			7,700	5,800
General and administrative amounts for certain government contracts remaining in inventory			400	500
Property, Plant and Equipment
Accumulated depreciation and amortization			(179,925)	(160,271)
Property, plant and equipment - net			160,547	144,969
Proceeds from sale of property, plant and equipment	$ 44,891	$ 44,891
Deferred Compensation Plan
Deferred compensation			10,900	11,000
Carrying value of Rabbi trust to fund deferred compensation liabilities			6,400	6,400
Land and land improvements
Property, Plant and Equipment
Property, plant and equipment, Gross			7,362	7,348
Buildings and improvements
Property, Plant and Equipment
Property, plant and equipment, Gross			48,628	48,191
Machinery and other equipment
Property, Plant and Equipment
Property, plant and equipment, Gross			125,656	107,297
Software
Property, Plant and Equipment
Property, plant and equipment, Gross			114,172	108,526
Leasehold improvements
Property, Plant and Equipment
Property, plant and equipment, Gross			20,346	17,064
Construction and internal-use software development in progress
Property, Plant and Equipment
Property, plant and equipment, Gross			$ 24,308	$ 16,814