v2.4.0.6

Commitments and Contingencies (Loss Contingency) (Details) (USD $) In Millions, unless otherwise specified |  |  | 12 Months Ended | 1 Months Ended | 12 Months Ended | 1 Months Ended | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2012 action | Aug. 31, 2008 Purse Enhancement Agreement | Dec. 31, 2012 Atlantic City | Feb. 28, 2009 County Assessor Property Tax Assessment | Dec. 31, 2007 County Assessor Property Tax Assessment | Dec. 31, 2011 County Assessor Property Tax Assessment | Dec. 31, 2007 Borgata | Dec. 31, 2012 Borgata | Dec. 31, 2011 Borgata | Dec. 31, 2010 Borgata | Aug. 31, 2008 Borgata | Dec. 31, 2010 Borgata Purse Enhancement Agreement | Dec. 31, 2012 Borgata Purse Enhancement Agreement property | Dec. 31, 2012 Borgata Atlantic City | Dec. 31, 2011 Borgata Atlantic City | Dec. 31, 2012 Borgata New Jersey Casino Control Act Investment Alternative Tax Assessment | Dec. 31, 2012 Borgata CRDA Investment Alternative Tax Assessment | Dec. 31, 2009 State of Nevada Department of Taxation Sales and Use Tax Deficiency
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of legal actions brought against company to date | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount of assessment by taxing authority |  |  |  |  | $ 6.2 |  |  |  |  |  |  |  |  |  |  |  |  | $ 12.3
Amount of interest assessed by taxing authority |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7.5
Increase in assessed property value, percentage |  |  |  |  | 400.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Amount of increase (decrease) of initial tax assessment by taxing authority |  |  |  | (2.2) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Property tax settlement, reduction in property tax accrual |  |  |  |  |  | 9.7 |  |  |  |  |  |  |  |  |  |  |  |
Investment Alternative Tax: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
New Jersey annual investment alternative tax, percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.25% | 2.50% |
Term of New Jersey Casino Reinvestment Development Authority (CRDA) bonds |  |  |  |  |  |  | 20 years | 50 years |  |  |  |  |  |  |  |  |  |
New Jersey Casino Reinvestment Development Authority (CRDA) obligation |  |  |  |  |  |  |  | 7.7 | 8.1 | 8.1 |  |  |  |  |  |  |  |
New Jersey Casino Reinvestment Development Authority (CRDA) obligation, valuation provision recorded |  |  |  |  |  |  |  | 4.4 | 3.5 | 4.6 |  |  |  |  |  |  |  |
Purse Enhancement Agreement: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of casinos participating in Purse Enhancement Agreement |  |  |  |  |  |  |  |  |  |  |  |  | 10 |  |  |  |  |
Obligation of all participating casinos, total |  | 90 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Borgata's pro rata share of Purse Enhancement Agreement obligation |  |  |  |  |  |  |  |  |  |  | 15.0 |  |  |  |  |  |  |
Atlantic City Tourism District [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Initial term of Atlantic City Alliance (ACA) assessment |  |  |  |  |  |  |  |  |  |  |  |  |  | 5 years |  |  |  |
ACA total five-year assessment by all casinos plus initial contribution |  |  | 155 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Atlantic City Alliance initial contribution |  |  | 5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
ACA annual assessment by all casinos |  |  | 30 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Expense under the agreement recorded in period |  |  |  |  |  |  |  |  |  |  |  | $ 5.1 |  | $ 6.1 | $ 0.9 |  |  |

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