Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenue recognition
Promotional allowances	$ 39,579	$ 37,782	$ 115,667	$ 112,404
Cost of complimentary services	13,246	12,775	38,365	38,512
Gaming and Racing Taxes
Gaming expense	259,400	221,500	730,900	661,500
Rooms
Revenue recognition
Promotional allowances	8,649	8,644	25,888	25,140
Cost of complimentary services	1,085	930	2,999	2,690
Food and beverage
Revenue recognition
Promotional allowances	28,245	26,518	82,896	79,907
Cost of complimentary services	11,280	10,945	32,761	33,161
Other
Revenue recognition
Promotional allowances	2,685	2,620	6,883	7,357
Cost of complimentary services	$ 881	$ 900	$ 2,605	$ 2,661
Master Lease Agreement
Spin-Off of Real Estate Assets through a Real Estate Investment Trust
Discount rate			9.70%
Lease term			35 years

Stated interest rate of the capital lease.

No definition available.

Name:	penn_CapitalLeasesInterestRate
Namespace Prefix:	penn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the estimated cost of providing complimentary services during the period.

+ References

No definition available.

+ Details

Name:	penn_CostOfComplimentaryServices
Namespace Prefix:	penn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

Name:	penn_GamingAndRacingTaxesAbstract
Namespace Prefix:	penn_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents gaming taxes, pari-mutuel taxes and purse expense.

+ References

No definition available.

+ Details

Name:	penn_GamingExpense
Namespace Prefix:	penn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	penn_LesseeLeasingArrangementsCapitalLeasesTermOfContract
Namespace Prefix:	penn_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	penn_SpinOffOfRealEstateAssetsThroughRealEstateInvestmentTrustDisclosureAbstract
Namespace Prefix:	penn_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the estimated retail value of accommodations, food and beverage, and other services furnished to guests without charge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 924
-SubTopic 605
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=51665414&loc=d3e51325-107943

+ Details

Name:	us-gaap_PromotionalAllowances
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_ProductOrServiceAxis=penn_FoodAndBeverageMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ProductOrServiceAxis=penn_OtherServicesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	penn_OperatingLeasesByTypeAxis=penn_MasterLeaseAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: