Basis of Presentation and Principles of Consolidation Basis of Presentation and Principles of Consolidation - Assets and Liabilities Classified as Held for Sale (Details) - Disposal Group, Held-for-sale, Not Discontinued Operations [Member] - Emerald Resort & Casino, South Africa disposition [Member] $ in Millions	Jun. 30, 2019 USD ($)
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents	$ 4
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment, Current	26
Disposal Group, Including Discontinued Operation, Goodwill	5
Disposal Group, Including Discontinued Operation, Intangible Assets	11
Disposal Group, Including Discontinued Operation, Other Assets	2
Disposal Group, Including Discontinued Operation, Assets, Current	48
Disposal Group, Including Discontinued Operation, Other Liabilities, Current	4
Disposal Group, Including Discontinued Operation, Accrued Liabilities, Current	3
Disposal Group, Including Discontinued Operation, Liabilities, Current	$ 7