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Organization and Description of Business (Details) - Operating partnership
Sep. 30, 2019
Dec. 31, 2018
Coresite Realty Corporation    
Organization    
Percentage of ownership interests held by the entity 77.60% 75.80%
Noncontrolling interests    
Organization    
Percentage of ownership interests held by others 22.40% 24.20%
Carlyle Group    
Organization    
Percentage of ownership interests held by others 22.40%