DISPOSITIONS AND ACQUISITIONS - Starwood Fair Value and Estimated Useful Lives of Identifiable Intangible Assets (Details) - Starwood Hotels & Resorts $ in Millions	Sep. 23, 2016 USD ($)
Business Acquisition [Line Items]
Estimated Fair Value (in millions)	$ 7,238
Management Agreements and Lease Contract Intangibles
Business Acquisition [Line Items]
Estimated Fair Value (in millions)	$ 751
Management Agreements and Lease Contract Intangibles \| Minimum
Business Acquisition [Line Items]
Estimated Useful Life (in years)	10 years
Management Agreements and Lease Contract Intangibles \| Maximum
Business Acquisition [Line Items]
Estimated Useful Life (in years)	25 years
Franchise Agreements
Business Acquisition [Line Items]
Estimated Fair Value (in millions)	$ 746
Franchise Agreements \| Minimum
Business Acquisition [Line Items]
Estimated Useful Life (in years)	10 years
Franchise Agreements \| Maximum
Business Acquisition [Line Items]
Estimated Useful Life (in years)	80 years
Loyalty Program Marketing Rights
Business Acquisition [Line Items]
Estimated Fair Value (in millions)	$ 77
Estimated Useful Life (in years)	30 years
Brands
Business Acquisition [Line Items]
Estimated Fair Value (in millions)	$ 5,664

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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