v3.25.4
Cover Page - USD ($)
$ / shares in Units, $ in Billions
 12 Months Ended
Dec. 31, 2025
Feb. 13, 2026
Jun. 30, 2025
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2025    
Document Transition Report false    
Entity File Number 001-37994    
Entity Registrant Name JBG SMITH PROPERTIES    
Entity Incorporation, State or Country Code MD    
Entity Tax Identification Number 81-4307010    
Entity Address, Address Line One 4747 Bethesda Avenue    
Entity Address, Address Line Two Suite 200    
Entity Address, City or Town Bethesda    
Entity Address, State or Province MD    
Entity Address, Postal Zip Code 20814    
City Area Code 240    
Local Phone Number 333-3600    
Title of 12(b) Security Common Shares, par value $0.01 per share    
Trading Symbol JBGS    
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    
Document Financial Statement Error Correction [Flag] false    
Entity Shell Company false    
Entity Public Float     $ 1.1
Share Price     $ 17.3
Documents Incorporated by Reference [Text Block]

Part III incorporates by reference information from certain portions of the registrant's definitive proxy statement for its 2026 annual meeting of shareholders to be filed with the Securities and Exchange Commission within 120 days after the end of the fiscal year to which this report relates.

    
Entity Central Index Key 0001689796    
Current Fiscal Year End Date --12-31    
Document Fiscal Year Focus 2025    
Document Fiscal Period Focus FY    
Amendment Flag false    
Auditor Name Deloitte & Touche LLP    
Auditor Firm ID 34    
Auditor Location McLean, Virginia    
Common shares      
Entity Common Stock, Shares Outstanding   58,951,982  
Class B Common Shares      
Entity Common Stock, Shares Outstanding   16,583,947