Diamond Acquisition - Schedule of Preliminary Estimates Of The Fair Value of Intangible Assets and Estimated Remaining Use (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ (150)	$ (102)
Diamond Acquisition
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	1,906
Trade name | Diamond Acquisition
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 20
Estimated Useful Life	1 year
Management contracts | Diamond Acquisition
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 1,263
Estimated Useful Life	17 years 6 months
Club member relationships | Diamond Acquisition
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 146
Estimated Useful Life	10 years
Vacation ownership customer relationships | Diamond Acquisition
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 463
Estimated Useful Life	5 years 6 months
Computer software | Diamond Acquisition
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 14
Estimated Useful Life	1 year 6 months