v3.25.2

LONG-TERM DEBT - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended
	Feb. 28, 2025	Jun. 30, 2025	Jun. 30, 2024
Debt Instrument [Line Items]
Interest paid, net of amounts capitalized		$ 328	$ 303
Maximum aggregate borrowings under credit facility (up to)		4,500
Series RR and SS Notes \| Senior Notes
Debt Instrument [Line Items]
Proceeds from debt	$ 1,960
Series RR Notes, maturing April 15, 2032
Debt Instrument [Line Items]
Senior notes, face amount		$ 500
Interest rate		5.10%
Series RR Notes, maturing April 15, 2032 \| Senior Notes
Debt Instrument [Line Items]
Senior notes, face amount	$ 500
Interest rate	5.10%
Series SS Notes, maturing April 15, 2037
Debt Instrument [Line Items]
Senior notes, face amount		$ 1,500
Interest rate		5.50%
Series SS Notes, maturing April 15, 2037 \| Senior Notes
Debt Instrument [Line Items]
Senior notes, face amount	$ 1,500
Interest rate	5.50%
Series SS Notes, maturing April 15, 2037 \| Senior Notes \| Interest Rate Swap
Debt Instrument [Line Items]
Derivative liability	$ 700
Derivative, basis spread on variable rate	1.49%

Face (par) amount of debt instrument at time of issuance.

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MARRIOTT INTERNATIONAL INC /MD/ 10-Q