ORGANIZATION OF THE PARENT COMPANY AND THE OPERATING PARTNERSHIP - Summary of Core Portfolio of Operating Properties and Excludes Development, Redevelopment and Held for Sale (Details)	Mar. 31, 2022 ft² property
Real Estate Properties [Line Items]
Number of Properties | property	81
Rentable area (in square feet) | ft²	13,678,136
Office properties
Real Estate Properties [Line Items]
Number of Properties | property	72
Rentable area (in square feet) | ft²	12,097,300
Mixed-use properties
Real Estate Properties [Line Items]
Number of Properties | property	5
Rentable area (in square feet) | ft²	942,334
Core Properties
Real Estate Properties [Line Items]
Number of Properties | property	77
Rentable area (in square feet) | ft²	13,039,634
Development property
Real Estate Properties [Line Items]
Number of Properties | property	1
Rentable area (in square feet) | ft²	205,803
Redevelopment properties
Real Estate Properties [Line Items]
Number of Properties | property	3
Rentable area (in square feet) | ft²	432,699