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Document And Entity Information
6 Months Ended
Jun. 30, 2012
Aug. 01, 2013
Document And Entity Information [Abstract]    
Document Type 10-Q  
Document Period End Date Jun. 30, 2013  
Document Fiscal Year Focus 2013  
Document Fiscal Period Focus Q2  
Entity Registrant Name BOSTON PROPERTIES INC  
Amendment Flag false  
Entity Central Index Key 0001037540  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   152,388,954