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Goodwill and Other Intangible Assets - Changes in Carrying Value of Goodwill by Segment (Details) - USD ($) $ in Millions		12 Months Ended
	Jul. 16, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Beginning balance		$ 7,539	$ 7,267
Beginning balance, Accumulated Impairment		(3,495)	(3,452)
Other			(3)
Transferred to assets held for sale		(5)
Impairment		(27)	(43)	$ 0
Ending balance		7,534	7,539	7,267
Ending balance, Accumulated Impairment		(3,522)	(3,495)	(3,452)
Net Carrying Value of Goodwill		4,012	4,044
Las Vegas
Goodwill [Roll Forward]
Beginning balance		6,204	6,204
Beginning balance, Accumulated Impairment		(3,115)	(3,115)
Other			0
Transferred to assets held for sale		0
Impairment		0	0
Ending balance		6,204	6,204	6,204
Ending balance, Accumulated Impairment		(3,115)	(3,115)	(3,115)
Net Carrying Value of Goodwill		3,089	3,089
Zero or negative carrying amount of goodwill		405
Other U.S.
Goodwill [Roll Forward]
Beginning balance		1,277	1,002
Beginning balance, Accumulated Impairment		(354)	(337)
Other			0
Transferred to assets held for sale		0
Impairment		(27)	(17)
Ending balance		1,277	1,277	1,002
Ending balance, Accumulated Impairment		(381)	(354)	(337)
Net Carrying Value of Goodwill		896	923
Zero or negative carrying amount of goodwill		81
All Other
Goodwill [Roll Forward]
Beginning balance		58	61
Beginning balance, Accumulated Impairment		(26)	0
Other			(3)
Transferred to assets held for sale		(5)
Impairment		0	(26)
Ending balance		53	58	61
Ending balance, Accumulated Impairment		(26)	(26)	$ 0
Net Carrying Value of Goodwill		$ 27	32
Centaur Holdings, LLC
Goodwill [Roll Forward]
Centaur acquisition			275
Centaur Holdings, LLC \| Las Vegas
Goodwill [Roll Forward]
Centaur acquisition			0
Centaur Holdings, LLC \| Other U.S.
Goodwill [Roll Forward]
Centaur acquisition	$ 275		275
Centaur Holdings, LLC \| All Other
Goodwill [Roll Forward]
Centaur acquisition			$ 0