Real Estate Activities Real Estate Activities - Acquisitions and Dispositions(Details) (USD $)	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Liabilities related to future tenant improvements	$ 14,800,000
Deferred costs and other assets	87,653,000us-gaap_DeferredCostsAndOtherAssets	87,017,000us-gaap_DeferredCostsAndOtherAssets
Springfield Town Center [Member]
Property, Plant and Equipment [Line Items]
Business Combination, Consideration	486,604,000
Assumption and payoff of long term debt	263,800,000
Land	119,934,000
Other significant noncash transaction, consideration given, OP Units	6,250,000
Buildings and Improvements, Gross	315,845,000
Land Improvements	36,424,000
Finite-Lived Intangible Asset, Acquired-in-Place Leases	18,126,000
Above Market Lease Gross	260,000
Below Market Lease, Acquired	(393,000)
Ground Leases, Gross	(5,882,000)
Deferred costs and other assets	2,290,000
Accrued Liabilities and Other Liabilities	$ 7,700,000

Above Market Lease Gross

No definition available.

Name:	pei_AboveMarketLeaseGross
Namespace Prefix:	pei_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Assumption and payoff of long term debt

+ References

No definition available.

+ Details

Name:	pei_Assumptionandpayoffoflongtermdebt
Namespace Prefix:	pei_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Business Combination, Consideration

+ References

No definition available.

+ Details

Name:	pei_BusinessCombinationConsideration
Namespace Prefix:	pei_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Liabilities related to future tenant improvements

+ References

No definition available.

+ Details

Name:	pei_Liabilitiesrelatedtofuturetenantimprovements
Namespace Prefix:	pei_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Other significant noncash transaction, consideration given, OP Units

+ References

No definition available.

+ Details

Name:	pei_OthersignificantnoncashtransactionconsiderationgivenOPUnits
Namespace Prefix:	pei_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Present value of additional consideration

+ References

No definition available.

+ Details

Name:	pei_Presentvalueofadditionalconsideration
Namespace Prefix:	pei_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of acquired leases acquired as part of a real property acquisition at below market lease rate with a finite life.

+ References

No definition available.

+ Details

Name:	us-gaap_BelowMarketLeaseAcquired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 4

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765

+ Details

Name:	us-gaap_BuildingsAndImprovementsGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Aggregate carrying amount of deferred costs and other assets not separately disclosed.

+ References

No definition available.

+ Details

Name:	us-gaap_DeferredCostsAndOtherAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the amount of value allocated by a lessor (acquirer) to lease agreements which exist at acquisition of a leased property. Such amount may include the value assigned to existing tenant relationships and excludes the market adjustment component of the value assigned for above or below-market leases acquired.

+ References

No definition available.

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetAcquiredInPlaceLeases
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Gross long-term land leases capitalized as part of real property.

+ References

No definition available.

+ Details

Name:	us-gaap_GroundLeasesGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 4

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_Land
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before accumulated deprecation and depletion of additions or improvements to real estate held for productive use. Examples include, but are not limited to, walkways, driveways, fences, and parking lots.

+ References

No definition available.

+ Details

Name:	us-gaap_LandImprovements
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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

- Details

Name:	us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=pei_SpringfieldTownCenterMember
Namespace Prefix:
Data Type:	na
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