v3.25.1
Cover Page - shares
 3 Months Ended
Mar. 31, 2025
Apr. 29, 2025
Document Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Mar. 31, 2025  
Document Transition Report false  
Entity File Number 001-34364  
Entity Registrant Name OFFICE PROPERTIES INCOME TRUST  
Entity Incorporation, State or Country Code MD  
Entity Tax Identification Number 26-4273474  
Entity Address, Address Line One Two Newton Place,  
Entity Address, Address Line Two 255 Washington Street,  
Entity Address, Address Line Three Suite 300,  
Entity Address, City or Town Newton,  
Entity Address, State or Province MA  
Entity Address, Postal Zip Code 02458-1634  
City Area Code 617  
Local Phone Number 219-1440  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   70,894,950
Entity Central Index Key 0001456772  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q1  
Common shares    
Document Information [Line Items]    
Title of 12(b) Security Common Shares of Beneficial Interest  
Trading Symbol OPI  
Security Exchange Name NASDAQ  
Senior unsecured notes, 6.375% interest rate, due in 2050    
Document Information [Line Items]    
Title of 12(b) Security 6.375% Senior Notes due 2050  
Trading Symbol OPINL  
Security Exchange Name NASDAQ