Consolidated Variable Interest Entities ("VIEs") and Investments in Affiliates - Schedule of Investments in Affiliates (Detail) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Schedule Of Equity Method Investments [Line Items]
Investments in affiliates		$ 52	$ 50
Hilton San Diego Bayfront [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership Percentage		25.00%
Investments in affiliates		$ 20	19
All others (7 hotels) [Member]
Schedule Of Equity Method Investments [Line Items]
Investments in affiliates	[1]	$ 32	$ 31
All others (7 hotels) [Member] | Minimum [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership Percentage		20.00%
All others (7 hotels) [Member] | Maximum [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership Percentage	[1]	50.00%

[1] ^{In July 2019, we and the other owners of the entity that own the Conrad Dublin, entered into an agreement to sell the ownership interest in the entity for a gross sales price of approximately $127 million, which is payable in cash at closing and is subject to customary pro rations and adjustments.  Our pro rata share of the gross sales price is approximately $61 million and our pro rata share of debt associated with the Conrad Dublin was $9 million as of September 30, 2019.  The sale is subject to customary closing conditions and required regulatory approvals and is currently anticipated to close in the fourth quarter of 2019. The basis in our interest in the Conrad Dublin was $7 million as of September 30, 2019 and December 31, 2018.}