v3.26.1
Document and Entity Information - $ / shares
 3 Months Ended
Mar. 31, 2026
Apr. 22, 2026
Dec. 31, 2025
Document Information [Line Items]      
Document Type 10-Q    
Amendment Flag false    
Document Period End Date Mar. 31, 2026    
Document Fiscal Year Focus 2026    
Document Fiscal Period Focus Q1    
Trading Symbol CURB    
Entity File Number 1-42265    
Entity Tax Identification Number 93-4224532    
Entity Address, Address Line One 320 Park Avenue    
Entity Address, City or Town New York    
Entity Address, Postal Zip Code 10022    
City Area Code 216    
Local Phone Number 755-5500    
Entity Address, State or Province NY    
Entity Registrant Name Curbline Properties Corp.    
Entity Central Index Key 0002027317    
Current Fiscal Year End Date --12-31    
Entity Filer Category Large Accelerated Filer    
Common Stock, Par or Stated Value Per Share $ 0.01   $ 0.01
Document Quarterly Report true    
Document Transition Report false    
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Shell Company false    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Incorporation, State or Country Code MD    
Security Exchange Name NYSE    
Title of 12(b) Security Common Stock    
Entity Common Stock, Shares Outstanding   105,539,344