Business Segments - Narrative (Details) $ in Millions	3 Months Ended
Dec. 31, 2021 USD ($) nationalPark segment	Jan. 01, 2021 USD ($)
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 \| $	$ 9.0	$ 10.0
Sales \| Food Services \| Product Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percentage	71.00%
Sales \| Facilities & Other \| Product Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percentage	29.00%

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