BUSINESS SEGMENTS - Reconciliation of Total Segment Revenue and Profit to Consolidated Revenue and Profit (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total revenue	$ 6,489	$ 6,255	$ 19,496	$ 18,671
Interest expense, net of interest income	(194)	(168)	(568)	(485)
INCOME BEFORE INCOME TAXES	994	786	2,812	2,553
Total reportable segment revenue
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total revenue	5,743	5,603	17,379	16,752
Operating income	945	881	2,860	2,759
Unallocated corporate and other
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total revenue	746	652	2,117	1,919
Operating income	$ 243	$ 73	$ 520	$ 279

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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+ Details

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details

MARRIOTT INTERNATIONAL INC /MD/ 10-Q