Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2017

Accounting Policies [Abstract]

Restrictions on Cash and Cash Equivalents [Table Text Block]

Reconciliation to Statements of Cash Flows
	As of December 31,
(In millions)	2017		2016
Cash and cash equivalents	$	2,558	$	1,540
Restricted cash, current	116		3,113
Restricted cash, non-current	35		5
Total cash, cash equivalents, and restricted cash	$	2,709	$	4,658

Property, Plant and Equipment, Estimated Useful Lives [Table Text Block]

Useful Lives
Land improvements			12	years
Buildings	20	to	40	years
Building and leasehold improvements	5	to	20	years
Riverboats and barges			30	years
Furniture, fixtures, and equipment	2.5	to	20	years