ACCUMULATED OTHER COMPREHENSIVE LOSS AND STOCKHOLDERS’ DEFICIT - Accumulated Other Comprehensive (Loss) Income Activity (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2025	Jun. 30, 2024
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance at beginning of period	$ (3,168)	$ (2,992)	$ (1,616)	$ (682)	$ (2,992)	$ (682)
Other comprehensive income (loss)	288	101	(111)	(147)	389	(258)
Balance at end of period	(2,964)	(3,168)	(2,091)	(1,616)	(2,964)	(2,091)
Intra-entity foreign currency long-term-investment (losses) gains					68	21
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance at beginning of period	(962)	(1,063)	(794)	(647)	(1,063)	(647)
Other comprehensive income (loss)	288	101	(111)	(147)
Balance at end of period	(674)	(962)	(905)	(794)	(674)	(905)
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance at beginning of period		(1,091)		(654)	(1,091)	(654)
Other comprehensive income (loss)					420	(271)
Balance at end of period	(671)		(925)		(671)	(925)
Other Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance at beginning of period		$ 28		$ 7	28	7
Other comprehensive income (loss)					(31)	13
Balance at end of period	$ (3)		$ 20		$ (3)	$ 20

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

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+ Details

MARRIOTT INTERNATIONAL INC /MD/ 10-Q