PARTY-IN-INTEREST (Details) - EBP 004 - Common stock - Marriott International, Inc. - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Number of shares held (in shares)	6,298,121	7,111,418
Dividend income	$ 18,659,067
Net asset value per share (in dollars per share)	$ 310.24	$ 278.94
Investment acquired, number of shares (in shares)	297,793
Investment acquired	$ 81,215,839
Investment sold, number of shares (in shares)	1,111,090
Investment sold	$ 310,878,634

Amount of increase in net asset available for benefit from dividend income on investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Cost of investment, excluding plan interest in master trust, acquired by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Number of shares or units of investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Net asset value per share or per unit of investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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