PARTY-IN-INTEREST (Details) - EBP 001 - Marriott International, Inc. common stock - 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)	12,906	13,341
Dividend income	$ 35,819
Net asset value per share (in dollars per share)	$ 310.24	$ 278.94
Investment acquired, number of shares (in shares)	1,486
Investment acquired	$ 392,464
Investment sold, number of shares (in shares)	1,921
Investment sold	$ 532,831

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

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Amount of selling price for investment, excluding plan interest in master trust, sold 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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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.

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