The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The cash outflow associated with the acquisition of a controlling interest in another entity or an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, joint venture or equity method investment).

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INTANGIBLE ASSETS AND GOODWILL (Details) - USD ($) $ in Millions		3 Months Ended
	Nov. 30, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Finite-lived intangible assets
Gross Carrying Amount		$ 3,120		$ 3,126
Accumulated Amortization		(1,042)		(1,001)
Net Carrying Amount		2,078		2,125
Amortization expense		45	$ 47
Supply and distribution agreements
Finite-lived intangible assets
Gross Carrying Amount		1,095		1,099
Accumulated Amortization		(422)		(408)
Net Carrying Amount		673		691
Technology
Finite-lived intangible assets
Gross Carrying Amount		173		173
Accumulated Amortization		(125)		(121)
Net Carrying Amount		48		52
Patents
Finite-lived intangible assets
Gross Carrying Amount		2		2
Accumulated Amortization		(2)		(2)
Net Carrying Amount		$ 0		0
Amortization Period		15 years
Internet domain names
Finite-lived intangible assets
Gross Carrying Amount		$ 40		41
Accumulated Amortization		(30)		(30)
Net Carrying Amount		10		11
Trade Names
Finite-lived intangible assets
Gross Carrying Amount		1,810		1,810
Accumulated Amortization		(463)		(439)
Net Carrying Amount		1,347		1,371
Noncompete Agreements
Finite-lived intangible assets
Gross Carrying Amount		0		1
Accumulated Amortization		0		(1)
Net Carrying Amount		$ 0		$ 0
Minimum \| Supply and distribution agreements
Finite-lived intangible assets
Amortization Period		3 years
Minimum \| Technology
Finite-lived intangible assets
Amortization Period		1 year
Minimum \| Internet domain names
Finite-lived intangible assets
Amortization Period		5 years
Minimum \| Trade Names
Finite-lived intangible assets
Amortization Period		4 years
Maximum \| Supply and distribution agreements
Finite-lived intangible assets
Amortization Period		20 years
Maximum \| Technology
Finite-lived intangible assets
Amortization Period		7 years
Maximum \| Internet domain names
Finite-lived intangible assets
Amortization Period		20 years
Maximum \| Trade Names
Finite-lived intangible assets
Amortization Period		20 years
HotelsCombined [Member]
Finite-lived intangible assets
Cash paid in business acquisition	$ 134