Business Segments - Narrative (Details) $ in Millions	6 Months Ended
Mar. 31, 2023 USD ($) segment nationalPark	Apr. 01, 2022 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	3
Possessory interest in National Park service sites \| nationalPark	1
Cost of services provided \| FSS United States
Segment Reporting Information [Line Items]
Proceeds from recovery of investment \| $	$ 19.8	$ 9.0
Food Services \| Sales \| Product Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percentage	73.00%
Facilities & Other \| Sales \| Product Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percentage	27.00%

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of realized and unrealized gain (loss) on investment.

+ References

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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