Summary of Significant Accounting Policies - Property, Equipment and Capitalized Software Costs - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 26, 2020	Sep. 25, 2020
Software Development \| Minimum [Member]
Property Plant And Equipment [Line Items]
Property, equipment and capitalized software, useful life		3 years
Software Development \| Maximum [Member]
Property Plant And Equipment [Line Items]
Property, equipment and capitalized software, useful life		5 years
Building \| Buffalo, NY [Member]
Property Plant And Equipment [Line Items]
Book value of building	$ 1.6
Proceeds from sale of building	2.5
Gain on sale of building	$ 0.8

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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The cash inflow from sale of buildings.

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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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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