Real Estate - Development/Redevelopment Narrative (Details) $ in Thousands	9 Months Ended
Sep. 30, 2020 USD ($) unit	Dec. 31, 2019 USD ($)
Real Estate [Line Items]
Properties under development or held for future development	$ 77,481	$ 124,193
The Trove
Real Estate [Line Items]
Total investment to date for property in development	$ 130,900
Number of units in property \| unit	401
Number of units in development project delivered \| unit	205
Assets placed into service	$ 83,600
Riverside Developments
Real Estate [Line Items]
Properties under development or held for future development	$ 28,200

The current amount of expenditures for a real estate project that has not yet been completed.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.10)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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

- Definition

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfUnitsInRealEstateProperty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- 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

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

- Definition

Assets Placed Into Service As Of Period End

+ References

No definition available.

+ Details

Name:	wre_AssetsPlacedIntoServiceAsOfPeriodEnd
Namespace Prefix:	wre_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Total investment to date in real estate property for development.

+ References

No definition available.

+ Details

Name:	wre_InvestmentInPropertyForDevelopment
Namespace Prefix:	wre_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number Of Units In Real Estate Property, Completed Construction And Delivered

+ References

No definition available.

+ Details

Name:	wre_NumberOfUnitsInRealEstatePropertyCompletedConstructionAndDelivered
Namespace Prefix:	wre_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=wre_TheTroveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=wre_RiversideDevelopmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: