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Organization and Basis of Presentation - Narrative (Details) $ in Billions | Mar. 31, 2021 USD ($) ft² property building
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Real Estate Properties [Line Items] |
Number of Real Estate Properties | property | 63
Under-construction assets |
Real Estate Properties [Line Items] |
Number of Real Estate Properties | property | 2
Near-term Development |
Real Estate Properties [Line Items] |
Number of Real Estate Properties | property | 9
Area of real estate property | ft² | 4,800,000
Future Development |
Real Estate Properties [Line Items] |
Number of Real Estate Properties | property | 29
Area of real estate property | ft² | 14,800,000
Commercial Real Estate |
Real Estate Properties [Line Items] |
Number of Real Estate Properties | property | 42
Area of real estate property | ft² | 13,300,000
Multifamily |
Real Estate Properties [Line Items] |
Number of Real Estate Properties | property | 21
Number of Units in Real Estate Property | building | 7,800
Multifamily | Under-construction assets |
Real Estate Properties [Line Items] |
Number of Units in Real Estate Property | building | 1,130
Wholly Owned Properties | Future Development |
Real Estate Properties [Line Items] |
Area of real estate property | ft² | 12,000,000.0
Wholly Owned Properties | Commercial Real Estate |
Real Estate Properties [Line Items] |
Area of real estate property | ft² | 11,400,000
Wholly Owned Properties | Multifamily |
Real Estate Properties [Line Items] |
Number of Units in Real Estate Property | building | 5,999
Wholly Owned Properties | Multifamily | Under-construction assets |
Real Estate Properties [Line Items] |
Number of Units in Real Estate Property | ft² | 969
Virginia Tech's |
Real Estate Properties [Line Items] |
Investments | $ | $ 1
JBG Smith, LP |
Real Estate Properties [Line Items] |
Ownership interest by parent | 90.50%

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