Long-Term Debt (Schedule of Long-term Debt) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Debt Instrument [Line Items]
Unamortized discount	$ (14,045,000)	$ (15,332,000)
Unamortized origination fees	(4,536,000)	(4,845,000)
Current maturities of long-term debt	27,688,000us-gaap_LongTermDebtCurrent	29,753,000us-gaap_LongTermDebtCurrent
Long-term debt, gross, excluding current maturities	3,394,678,000	3,451,815,000
Long-term debt, net of current maturities	3,376,097,000us-gaap_LongTermDebtNoncurrent	3,431,638,000us-gaap_LongTermDebtNoncurrent
Senior Notes \| 9.125% Senior Notes Due 2018
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			9.125%
Senior Notes \| 9.00% Senior Notes Due 2020
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			9.00%
Parent
Debt Instrument [Line Items]
Long-term Debt, Gross	2,347,190,000	2,389,165,000
Unamortized discount	(14,045,000)	(15,332,000)
Unamortized origination fees	(4,536,000)	(4,845,000)
Long-term debt, net	2,328,609,000	2,368,988,000
Current maturities of long-term debt	21,500,000	21,500,000
Long-term debt, net of current maturities	2,165,985,000	2,207,490,000
Parent \| Bank Credit Facility
Debt Instrument [Line Items]
Amount outstanding	1,345,450,000	1,387,425,000
Remaining borrowing capacity		304,500,000
Parent \| Bank Credit Facility \| Bank Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate at period end	3.676%	3.66%
Long-term Debt, Gross		1,387,425,000
Unamortized discount	(3,429,000)	(3,589,000)
Unamortized origination fees	0	0
Long-term debt, net		1,383,836,000
Parent \| Senior Notes \| 9.125% Senior Notes Due 2018
Debt Instrument [Line Items]
Long-term Debt, Gross		500,000,000
Unamortized discount	0	0
Unamortized origination fees	(4,536,000)	(4,845,000)
Long-term debt, net		495,155,000
Debt Instrument, Interest Rate, Stated Percentage	9.13%	9.13%
Parent \| Senior Notes \| 9.00% Senior Notes Due 2020
Debt Instrument [Line Items]
Long-term Debt, Gross		350,000,000
Unamortized discount	0	0
Unamortized origination fees	0	0
Long-term debt, net		350,000,000
Debt Instrument, Interest Rate, Stated Percentage	9.00%	9.00%
Parent \| Other \| Holdco Note [Member]
Debt Instrument [Line Items]
Interest rate at period end	8.00%	8.00%
Long-term Debt, Gross		151,740,000
Unamortized discount	(10,616,000)	(11,743,000)
Unamortized origination fees	0	0
Long-term debt, net		139,997,000
Subsidiary, Peninsula Gaming [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	1,075,176,000	1,092,403,000
Unamortized discount	0	0
Unamortized origination fees	0	0
Long-term debt, net	1,075,176,000	1,092,403,000
Subsidiary, Peninsula Gaming [Member] \| Bank Credit Facility
Debt Instrument [Line Items]
Amount outstanding	725,200,000
Remaining borrowing capacity		32,100,000
Subsidiary, Peninsula Gaming [Member] \| Bank Credit Facility \| Bank Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate at period end	4.25%	4.25%
Long-term Debt, Gross		742,400,000
Unamortized discount	0	0
Unamortized origination fees	0	0
Long-term debt, net		742,400,000
Subsidiary, Peninsula Gaming [Member] \| Senior Notes \| Peninsula Senior Notes due 2018 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		350,000,000
Unamortized discount	0	0
Unamortized origination fees	0	0
Long-term debt, net		350,000,000
Debt Instrument, Interest Rate, Stated Percentage	8.38%	8.38%
Subsidiary, Peninsula Gaming [Member] \| Other
Debt Instrument [Line Items]
Long-term Debt, Gross		3,000
Unamortized discount	0	0
Unamortized origination fees	0	0
Long-term debt, net		3,000
Consolidated, Excluding Borgata [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	3,422,366,000	3,481,568,000
Unamortized discount	(14,045,000)	(15,332,000)
Unamortized origination fees	(4,536,000)	(4,845,000)
Long-term debt, net	$ 3,403,785,000	$ 3,461,391,000

Debt Instrument, Unamortized Origination Fees

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Long-term Debt, Gross, Excluding Current Maturities

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The effective interest rate at the end of the reporting period.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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