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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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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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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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No definition available.

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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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Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Apr. 01, 2018	Mar. 31, 2019	Apr. 01, 2018	Sep. 30, 2018
Property and Equipment
Property and equipment, gross	$ 165,919		$ 165,919		$ 163,364
Accumulated depreciation	(124,259)		(124,259)		(120,086)
Property and equipment, net	41,660		41,660		43,278
Depreciation expense related to property and equipment	4,200	$ 5,100	8,500	$ 10,300
Equipment, furniture and fixtures
Property and Equipment
Property and equipment, gross	133,593		133,593		131,521
Leasehold improvements
Property and Equipment
Property and equipment, gross	31,915		31,915		31,430
Land and buildings
Property and Equipment
Property and equipment, gross	$ 411		$ 411		$ 413