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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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		9 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 27, 2021	Jun. 28, 2020	Jun. 27, 2021	Jun. 28, 2020	Sep. 27, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 134,569		$ 134,569		$ 125,511
Accumulated depreciation	(98,568)		(98,568)		(90,004)
Property and equipment, net	36,001		36,001		35,507
Depreciation expense related to property and equipment	3,100	$ 3,700	9,000	$ 10,100
Equipment, furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	98,289		98,289		90,942
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 36,280		$ 36,280		$ 34,569