| Document and Entity Information | Feb. 26, 2020 |
| Document And Entity Information [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Feb. 26, 2020 |
| Entity Registrant Name | Pennsylvania Real Estate Investment Trust |
| Entity Central Index Key | 0000077281 |
| Entity Emerging Growth Company | false |
| Entity File Number | 1-6300 |
| Entity Incorporation, State or Country Code | PA |
| Entity Tax Identification Number | 23-6216339 |
| Entity Address, Address Line One | One Commerce Square 2005 Market Street |
| Entity Address, Address Line Two | Suite 1000 |
| Entity Address, City or Town | Philadelphia |
| Entity Address, State or Province | PA |
| Entity Address, Postal Zip Code | 19103 |
| City Area Code | 215 |
| Local Phone Number | 875-0700 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Common Stock [Member] | |
| Document And Entity Information [Line Items] | |
| Title of 12(b) Security | Shares of Beneficial Interest |
| Trading Symbol | PEI |
| Security Exchange Name | NYSE |
| Preferred Shares [Member] | |
| Document And Entity Information [Line Items] | |
| Title of 12(b) Security | Preferred Shares |
| Trading Symbol | PEIPrB |
| Security Exchange Name | NYSE |
| Preferred Shares 2 [Member] | |
| Document And Entity Information [Line Items] | |
| Title of 12(b) Security | Preferred Shares |
| Trading Symbol | PEIPrC |
| Security Exchange Name | NYSE |
| Preferred Shares 1 [Member] | |
| Document And Entity Information [Line Items] | |
| Title of 12(b) Security | Preferred Shares |
| Trading Symbol | PEIPrD |
| Security Exchange Name | NYSE |
