Summary of Significant Accounting Policies - Impairment of Long-lived assets and Long-lived assets to be disposed of (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2020	Jun. 26, 2020
Property Plant And Equipment [Line Items]
Adjustment to reduce capital software	$ 0.8
Building \| Buffalo, NY [Member]
Property Plant And Equipment [Line Items]
Carrying value of property		$ 1.6
Proceeds from sale of property		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.

+ References

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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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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