XML 18 R1.htm IDEA: XBRL DOCUMENT v3.4.0.3
Document and Entity Information - shares
3 Months Ended
Mar. 31, 2016
Apr. 20, 2016
Entity Information [Line Items]    
Entity Registrant Name CORPORATE OFFICE PROPERTIES TRUST  
Entity Central Index Key 0000860546  
Document Type 10-Q  
Document Period End Date Mar. 31, 2016  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   94,650,659
Document Fiscal Year Focus 2016  
Document Fiscal Period Focus Q1  
Corporate Office Properties, L.P.    
Entity Information [Line Items]    
Entity Registrant Name CORPORATE OFFICE PROPERTIES, L.P.  
Entity Central Index Key 0001577966  
Document Type 10-Q  
Document Period End Date Mar. 31, 2016  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Entity Filer Category Non-accelerated Filer  
Document Fiscal Year Focus 2016  
Document Fiscal Period Focus Q1