REVENUE AND RECEIVABLES - Schedule of Sources of Revenue by Segment (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 1,272	$ 1,173	$ 3,665	$ 3,441
Cost reimbursements	446	451	1,276	1,231
Financing	95	90	279	268
TOTAL REVENUES	1,367	1,263	3,944	3,709
Sale of vacation ownership products
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	459	358	1,232	1,083
Ancillary revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	68	70	209	212
Management fee revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	56	57	171	170
Exchange and other services revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	88	87	273	266
Management and exchange
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	212	214	653	648
Rental
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	155	150	504	479
Operating segments
Disaggregation of Revenue [Line Items]
TOTAL REVENUES	1,360	1,263	3,924	3,697
Corporate and Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7	0	20	12
Cost reimbursements	(9)	(13)	(29)	(28)
Financing	0	0	0	0
TOTAL REVENUES	7	0	20	12
Corporate and Other \| Sale of vacation ownership products
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Corporate and Other \| Ancillary revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Corporate and Other \| Management fee revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	(1)	(1)	(2)	(2)
Corporate and Other \| Exchange and other services revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17	14	51	42
Corporate and Other \| Management and exchange
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	16	13	49	40
Corporate and Other \| Rental
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Vacation Ownership \| Operating segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,213	1,120	3,482	3,265
Cost reimbursements	451	462	1,293	1,253
Financing	95	90	279	268
TOTAL REVENUES	1,308	1,210	3,761	3,533
Vacation Ownership \| Operating segments \| Sale of vacation ownership products
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	459	358	1,232	1,083
Vacation Ownership \| Operating segments \| Ancillary revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	67	69	206	209
Vacation Ownership \| Operating segments \| Management fee revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	56	56	168	166
Vacation Ownership \| Operating segments \| Exchange and other services revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	34	33	105	103
Vacation Ownership \| Operating segments \| Management and exchange
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	157	158	479	478
Vacation Ownership \| Operating segments \| Rental
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	146	142	478	451
Exchange & Third-Party Management \| Operating segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	52	53	163	164
Cost reimbursements	4	2	12	6
Financing	0	0	0	0
TOTAL REVENUES	52	53	163	164
Exchange & Third-Party Management \| Operating segments \| Sale of vacation ownership products
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Exchange & Third-Party Management \| Operating segments \| Ancillary revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1	1	3	3
Exchange & Third-Party Management \| Operating segments \| Management fee revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1	2	5	6
Exchange & Third-Party Management \| Operating segments \| Exchange and other services revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	37	40	117	121
Exchange & Third-Party Management \| Operating segments \| Management and exchange
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	39	43	125	130
Exchange & Third-Party Management \| Operating segments \| Rental
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 9	$ 8	$ 26	$ 28