Acquisitions, Investments, Dispositions and Divestitures - Income from Discontinued Operations (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net revenues	$ 33.5	$ 93.3	$ 163.1	$ 268.5
Pre-tax income/(loss) from operations	(46.1)	(98.7)	(188.4)	(151.5)
Income/(loss), net of income taxes	(48.4)	(62.6)	(177.4)	(110.3)
Showboat Atlantic City [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net revenues	33.5	58.3	115.4	157.8
Pre-tax income/(loss) from operations	(23.8)	7.9	(36.2)	10.0
Income/(loss), net of income taxes	(26.1)	4.6	(25.2)	5.6
Harrahs Tunica [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net revenues	0	31.9	46.4	99.9
Pre-tax income/(loss) from operations	(22.7)	(120.8)	(119.1)	(130.4)
Income/(loss), net of income taxes	(22.7)	(78.3)	(119.1)	(84.5)
Other [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net revenues	0	3.1	1.3	10.8
Pre-tax income/(loss) from operations	0.4	14.2	(33.1)	(31.1)
Income/(loss), net of income taxes	$ 0.4	$ 11.1	$ (33.1)	$ (31.4)