Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 30, 2018	Dec. 31, 2017	Sep. 30, 2018
Property and Equipment
Property and equipment, gross	$ 163,900		$ 163,364
Accumulated depreciation	(122,105)		(120,086)
Property and equipment, net	41,795		43,278
Depreciation expense related to property and equipment	4,300	$ 5,200
Equipment, furniture and fixtures
Property and Equipment
Property and equipment, gross	132,162		131,521
Leasehold improvements
Property and Equipment
Property and equipment, gross	31,327		31,430
Land and buildings
Property and Equipment
Property and equipment, gross	$ 411		$ 413

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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