Vacation Ownership Contract Receivables (Summary Of The Aged Analysis Of Financing Receivables Using The Most Recently Updated FICO Scores) (Details) - USD ($) $ in Millions		Dec. 31, 2020	Dec. 31, 2019
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross	[1]	$ 3,175	$ 3,867
Financing Receivable, Contract Under Temporary Deferment		37	8
FICO Score, Greater than 700 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross	[1]	1,751	2,075
FICO Score, 600 to 699 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross	[1]	894	1,135
Fico Scores Less Than 600 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross	[1]	199	258
No Score [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross	[1]	106	145
Asia Pacific [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross	[1]	225	254
Current [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		3,018	3,648
Current [Member] | FICO Score, Greater than 700 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		1,706	2,019
Current [Member] | FICO Score, 600 to 699 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		835	1,049
Current [Member] | Fico Scores Less Than 600 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		160	196
Current [Member] | No Score [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		96	134
Current [Member] | Asia Pacific [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		221	250
31 - 60 Days [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		64	90
31 - 60 Days [Member] | FICO Score, Greater than 700 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		20	25
31 - 60 Days [Member] | FICO Score, 600 to 699 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		25	37
31 - 60 Days [Member] | Fico Scores Less Than 600 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		13	21
31 - 60 Days [Member] | No Score [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		4	5
31 - 60 Days [Member] | Asia Pacific [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		2	2
61 - 90 Days [Member
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		47	67
61 - 90 Days [Member | FICO Score, Greater than 700 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		13	18
61 - 90 Days [Member | FICO Score, 600 to 699 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		18	28
61 - 90 Days [Member | Fico Scores Less Than 600 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		12	17
61 - 90 Days [Member | No Score [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		3	3
61 - 90 Days [Member | Asia Pacific [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		1	1
91 - 120 Days [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		46	62
91 - 120 Days [Member] | FICO Score, Greater than 700 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		12	13
91 - 120 Days [Member] | FICO Score, 600 to 699 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		16	21
91 - 120 Days [Member] | Fico Scores Less Than 600 [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		14	24
91 - 120 Days [Member] | No Score [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		3	3
91 - 120 Days [Member] | Asia Pacific [Member]
Financing Receivables, Recorded Investment [Line Items]
Vacation ownership contract receivables, gross		$ 1	$ 1

[1] Includes contracts under temporary deferment (up to 180 days). As of December 31, 2020 and 2019, contracts under deferment total $37 million and $8 million.