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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Commitments and Contingencies - Contingent Purchase Obligations (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2017
Guarantor Obligations [Line Items]
Guarantee	$ 221
Guarantee, recorded liability	89
Sheraton Grand Chicago Hotel
Guarantor Obligations [Line Items]
Guarantee, recorded liability	300	$ 300
Sheraton Grand Chicago Hotel \| Hotel and Leasehold
Guarantor Obligations [Line Items]
Guarantee			$ 300
Sheraton Grand Chicago Hotel \| Land
Guarantor Obligations [Line Items]
Guarantee	$ 200