v2.4.0.8

Commitments and Contingencies (Loss Contingency) (Details) (USD $) In Millions, unless otherwise specified |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2013 action | Sep. 30, 2013 Property Tax Assessment | Dec. 31, 2009 State of Nevada Department of Taxation Sales and Use Tax Deficiency | Dec. 31, 2009 State of New Jersey Real Estate Taxes [Member] | Dec. 31, 2010 Subsidiary, Borgata Property Tax Assessment | Dec. 31, 2009 Subsidiary, Borgata Property Tax Assessment
Loss Contingencies [Line Items] |  |  |  |  |  |
Number of legal actions brought against company to date | 2 |  |  |  |  |
Amount of assessment by taxing authority |  |  | $ 12.3 | $ 2,300.0 |  |
Amount of interest assessed by taxing authority |  |  | 7.5 |  |  |
Increase in assessed property value, percentage |  | 46.00% |  |  |  |
Range of possible additional property tax obligation, minimum |  | 5.4 |  |  |  |
Range of possible additional tax obligation, maximum |  | 14.7 |  |  | 870.0 | 880.0
Accrual for potential property tax obligation |  | $ 14.7 |  |  |  |

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