Guarantor Obligations, Additional Exposure, Undiscounted

No definition available.

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Namespace Prefix:	mar_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

+ Details

Name:	us-gaap_GuaranteeObligationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

+ Details

Name:	us-gaap_GuaranteeObligationsMaximumExposure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	mar_LossContingenciesBySecondaryNatureOfContingencyAxis=mar_NotYetInEffectConditionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=mar_SheratonGrandChicagoHotelMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=mar_BuildingandLandLeaseholdMember
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Data Type:	na
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- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LandMember
Namespace Prefix:
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COMMITMENTS AND CONTINGENCIES - Contingent Purchase Obligations (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023	Dec. 31, 2017
Guarantor Obligations [Line Items]
Guarantee	$ 228
Guarantee, recorded liability	101
Operating profit
Guarantor Obligations [Line Items]
Guarantee	146
Guarantee, recorded liability	91
Not Yet In Effect Condition \| Operating profit
Guarantor Obligations [Line Items]
Guarantee	58
Sheraton Grand Chicago Hotel
Guarantor Obligations [Line Items]
Guarantee, recorded liability	300	$ 300
Sheraton Grand Chicago Hotel \| Hotel and Leasehold
Guarantor Obligations [Line Items]
Guarantee	500		$ 300
Sheraton Grand Chicago Hotel \| Land
Guarantor Obligations [Line Items]
Guarantor obligations, additional exposure	$ 200