SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) - Impact of Reclassification by Quarter (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reclassification [Line Items]
Sales and other expenses	$ 650	$ 807	$ 717	$ 570	$ 511	$ 609	$ 503	$ 363	$ 2,744	$ 1,986	$ 979
General and administrative	738	303	253	261	270	193	169	134	1,555	766	522
Previously Reported
Reclassification [Line Items]
Sales and other expenses	597	723	666	542	474	540	465	339	2,528	1,818	881
General and administrative	791	387	304	289	307	262	207	158	1,771	934	620
Reclassifications
Reclassification [Line Items]
Sales and other expenses	53	84	51	28	37	69	38	24	216	168	98
General and administrative	$ (53)	$ (84)	$ (51)	$ (28)	$ (37)	$ (69)	$ (38)	$ (24)	$ (216)	$ (168)	$ (98)

"Sales and other expenses" are generally variable in nature and consist primarily of: (1) credit cards and other payment processing fees associated with merchant transactions; (2) fees paid to third parties that provide call center, website content translations and other services; (3) provisions for customer chargebacks associated with merchant transactions; (4) customer relations costs; (5) provisions for credit losses and bad debt, primarily related to agency accommodation commission receivables; and (6) insurance claim costs.

No definition available.

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- Definition

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 205
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483504/205-10-50-1

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