Fair Value Measurements (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2015	Dec. 31, 2014
Hollywood Gaming at Dayton Raceway And Mahoning Valley Race Course
Financial assets:
Discount rate (as a percent)		5.00%
Carrying Amount
Financial assets:
Cash and Cash Equivalents	$ 223,489	$ 223,489	$ 208,673
Debt Instrument, Fair Value Disclosure	13,245	13,245	19,189
Fair Value
Financial assets:
Cash and Cash Equivalents	223,489	223,489	208,673
Debt Instrument, Fair Value Disclosure	13,245	13,245	19,189
Level 1
Financial assets:
Cash and Cash Equivalents	223,489	223,489	208,673
Level 3
Financial assets:
Debt Instrument, Fair Value Disclosure	13,245	13,245	19,189
Plainridge Racecourse \| General and administrative expenses
Financial assets:
Change in fair value of contingent purchase price consideration	6,700	5,900
Senior secured credit facility \| Carrying Amount
Financial assets:
Debt Instrument, Fair Value Disclosure	1,214,633	1,214,633	785,683
Senior secured credit facility \| Fair Value
Financial assets:
Debt Instrument, Fair Value Disclosure	1,230,292	1,230,292	799,556
Senior secured credit facility \| Level 1
Financial assets:
Debt Instrument, Fair Value Disclosure	840,292	840,292	714,556
Senior secured credit facility \| Level 2
Financial assets:
Debt Instrument, Fair Value Disclosure	390,000	390,000	85,000
Senior Unsecured Notes \| Carrying Amount
Financial assets:
Debt Instrument, Fair Value Disclosure	296,091	296,091	295,610
Senior Unsecured Notes \| Fair Value
Financial assets:
Debt Instrument, Fair Value Disclosure	303,000	303,000	276,000
Senior Unsecured Notes \| Level 1
Financial assets:
Debt Instrument, Fair Value Disclosure	303,000	303,000	276,000
Other long-term obligations \| Carrying Amount
Financial assets:
Debt Instrument, Fair Value Disclosure	146,992	146,992	135,000
Other long-term obligations \| Fair Value
Financial assets:
Debt Instrument, Fair Value Disclosure	145,644	145,644	135,000
Other long-term obligations \| Level 2
Financial assets:
Debt Instrument, Fair Value Disclosure	$ 145,644	$ 145,644	$ 135,000

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13476-108611

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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