Long-Term Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Unamortized discount	$ (11,110)	$ (15,332)
Unamortized origination fees	0	(4,845)
Current maturities of long-term debt	27,688	29,753
Long-term debt, gross, excluding current maturities	3,313,797	3,451,815
Long-term debt, net of current maturities	$ 3,302,687	3,431,638
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	$ 2,322,535	2,389,165
Unamortized discount	(11,110)	(15,332)
Unamortized origination fees	0	(4,845)
Long-term debt, net	2,311,425	2,368,988
Current maturities of long-term debt	21,500	21,500
Long-term debt, net of current maturities	2,140,372	2,207,490
Parent \| Bank Credit Facility
Debt Instrument [Line Items]
Amount outstanding	1,064,725	$ 1,387,425
Remaining borrowing capacity	$ 502,200
Parent \| Bank Credit Facility \| Bank Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate at period end	3.774%	3.66%
Unamortized discount	$ (2,853)	$ (3,589)
Unamortized origination fees	$ 0	0
Parent \| Senior Notes \| 9.125% Senior Notes Due 2018
Debt Instrument [Line Items]
Unamortized discount		0
Unamortized origination fees		$ (4,845)
Debt Instrument, Interest Rate, Stated Percentage	9.125%	9.125%
Parent \| Senior Notes \| 9.00% Senior Notes Due 2020
Debt Instrument [Line Items]
Unamortized discount	$ 0	$ 0
Unamortized origination fees	$ 0	$ 0
Debt Instrument, Interest Rate, Stated Percentage	9.00%	9.00%
Parent \| Senior Notes \| 6.875 % Senior Notes Due 2023
Debt Instrument [Line Items]
Unamortized discount	$ 0
Unamortized origination fees	$ 0
Debt Instrument, Interest Rate, Stated Percentage	6.875%
Parent \| Other \| Holdco Note [Member]
Debt Instrument [Line Items]
Interest rate at period end	8.00%	8.00%
Long-term Debt, Gross	$ 157,810	$ 143,000
Unamortized discount	(8,257)	(11,743)
Unamortized origination fees	0	0
Subsidiary, Peninsula Gaming [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	1,018,950	1,092,403
Unamortized discount	0	0
Unamortized origination fees	0	0
Long-term debt, net	1,018,950	1,092,403
Subsidiary, Peninsula Gaming [Member] \| Bank Credit Facility
Debt Instrument [Line Items]
Amount outstanding	668,950	$ 742,400
Remaining borrowing capacity	$ 32,600
Subsidiary, Peninsula Gaming [Member] \| Bank Credit Facility \| Bank Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate at period end	4.25%	4.25%
Unamortized discount	$ 0	$ 0
Unamortized origination fees	0	0
Subsidiary, Peninsula Gaming [Member] \| Senior Notes \| Peninsula Senior Notes due 2018 [Member]
Debt Instrument [Line Items]
Unamortized discount	0	0
Unamortized origination fees	$ 0	$ 0
Debt Instrument, Interest Rate, Stated Percentage	8.38%	8.38%
Subsidiary, Peninsula Gaming [Member] \| Other
Debt Instrument [Line Items]
Unamortized discount		$ 0
Unamortized origination fees		0
Consolidated, Excluding Borgata [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 3,341,485	3,481,568
Unamortized discount	(11,110)	(15,332)
Unamortized origination fees	0	(4,845)
Long-term debt, net	3,330,375	3,461,391
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Level 3 \| Parent
Debt Instrument [Line Items]
Commitments, Fair Value Disclosure	28,222	29,529
Outstanding Face Amount \| Fair Value, Measurements, Nonrecurring [Member] \| Level 2 \| Parent \| Bank Credit Facility \| Bank Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	1,064,725	1,387,425
Outstanding Face Amount \| Fair Value, Measurements, Nonrecurring [Member] \| Level 2 \| Subsidiary, Peninsula Gaming [Member] \| Bank Credit Facility \| Bank Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	668,950	742,400
Outstanding Face Amount \| Fair Value, Measurements, Nonrecurring [Member] \| Level 2 \| Subsidiary, Peninsula Gaming [Member] \| Senior Notes \| Peninsula Senior Notes due 2018 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	350,000	350,000
Outstanding Face Amount \| Fair Value, Measurements, Nonrecurring [Member] \| Level 1 \| Parent \| Senior Notes \| 9.125% Senior Notes Due 2018
Debt Instrument [Line Items]
Long-term Debt, Gross		500,000
Outstanding Face Amount \| Fair Value, Measurements, Nonrecurring [Member] \| Level 1 \| Parent \| Senior Notes \| 9.00% Senior Notes Due 2020
Debt Instrument [Line Items]
Long-term Debt, Gross	350,000	350,000
Outstanding Face Amount \| Fair Value, Measurements, Nonrecurring [Member] \| Level 1 \| Parent \| Senior Notes \| 6.875 % Senior Notes Due 2023
Debt Instrument [Line Items]
Long-term Debt, Gross	750,000
Outstanding Face Amount \| Fair Value, Measurements, Nonrecurring [Member] \| Level 3 \| Parent
Debt Instrument [Line Items]
Commitments, Fair Value Disclosure	35,378	36,749
Outstanding Face Amount \| Fair Value, Measurements, Nonrecurring [Member] \| Level 3 \| Parent \| Other \| Holdco Note [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		151,740
Outstanding Face Amount \| Fair Value, Measurements, Nonrecurring [Member] \| Level 3 \| Subsidiary, Peninsula Gaming [Member] \| Other
Debt Instrument [Line Items]
Long-term Debt, Gross		3
Carrying Value \| Parent
Debt Instrument [Line Items]
Long-term debt, net	2,311,425	2,368,988
Carrying Value \| Subsidiary, Peninsula Gaming [Member]
Debt Instrument [Line Items]
Long-term debt, net	1,018,950	1,092,403
Carrying Value \| Consolidated, Excluding Borgata [Member]
Debt Instrument [Line Items]
Long-term debt, net	3,330,375	3,461,391
Carrying Value \| Fair Value, Measurements, Nonrecurring [Member] \| Level 2 \| Parent \| Bank Credit Facility \| Bank Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt, net	1,061,872	1,383,836
Carrying Value \| Fair Value, Measurements, Nonrecurring [Member] \| Level 2 \| Subsidiary, Peninsula Gaming [Member] \| Bank Credit Facility \| Bank Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt, net	668,950	742,400
Carrying Value \| Fair Value, Measurements, Nonrecurring [Member] \| Level 2 \| Subsidiary, Peninsula Gaming [Member] \| Senior Notes \| Peninsula Senior Notes due 2018 [Member]
Debt Instrument [Line Items]
Long-term debt, net	350,000	350,000
Carrying Value \| Fair Value, Measurements, Nonrecurring [Member] \| Level 1 \| Parent \| Senior Notes \| 9.125% Senior Notes Due 2018
Debt Instrument [Line Items]
Long-term debt, net		495,155
Carrying Value \| Fair Value, Measurements, Nonrecurring [Member] \| Level 1 \| Parent \| Senior Notes \| 9.00% Senior Notes Due 2020
Debt Instrument [Line Items]
Long-term debt, net	350,000	350,000
Carrying Value \| Fair Value, Measurements, Nonrecurring [Member] \| Level 1 \| Parent \| Senior Notes \| 6.875 % Senior Notes Due 2023
Debt Instrument [Line Items]
Long-term debt, net	750,000
Carrying Value \| Fair Value, Measurements, Nonrecurring [Member] \| Level 3 \| Parent
Debt Instrument [Line Items]
Commitments, Fair Value Disclosure	27,742	28,612
Carrying Value \| Fair Value, Measurements, Nonrecurring [Member] \| Level 3 \| Parent \| Other \| Holdco Note [Member]
Debt Instrument [Line Items]
Long-term debt, net	$ 149,553	139,997
Carrying Value \| Fair Value, Measurements, Nonrecurring [Member] \| Level 3 \| Subsidiary, Peninsula Gaming [Member] \| Senior Notes \| Other
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 3

Debt Instrument, Unamortized Origination Fees

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Long-term Debt, Gross, Excluding Current Maturities

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Fair value portion of arrangements with third parties, including, but not limited to, operating lease arrangement and arrangement in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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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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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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