Annual report pursuant to Section 13 and 15(d)

Cover

v3.20.4
Cover - USD ($)
12 Months Ended
Dec. 31, 2020
Feb. 11, 2021
Jun. 30, 2020
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2020    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity File Number 001-06622    
Entity Registrant Name WASHINGTON REAL ESTATE INVESTMENT TRUST    
Entity Central Index Key 0000104894    
Document Fiscal Year Focus 2020    
Document Fiscal Period Focus FY    
Amendment Flag false    
Entity Incorporation, State or Country Code MD    
Entity Tax Identification Number 53-0261100    
Entity Address, Address Line One 1775 EYE STREET, NW    
Entity Address, Address Line Two SUITE 1000    
Entity Address, City or Town WASHINGTON    
Entity Address, State or Province DC    
Entity Address, Postal Zip Code 20006    
City Area Code 202    
Local Phone Number 774-3200    
Title of 12(b) Security Shares of Beneficial Interest    
Trading Symbol WRE    
Security Exchange Name NYSE    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag true    
Entity Shell Company false    
Entity Public Float     $ 1,811,606,216
Entity Common Stock, Shares Outstanding   84,559,065  
Documents Incorporated by Reference Portions of our definitive Proxy Statement relating to the 2021 Annual Meeting of Shareholders, to be filed with the Securities and Exchange Commission, are incorporated by reference in Part III, Items 10-14 of this Annual Report on Form 10-K as indicated herein.