Organization and Basis of Presentation - Narrative (Details) ft² in Millions, $ in Billions	12 Months Ended
Dec. 31, 2023 USD ($) ft² property item building
Real estate properties
Number of Real Estate Properties	44
Number of key demand drivers \| item	4
National Landing Submarket in Northern Virginia
Real estate properties
Percentage of operating portfolio by the entity	75.00%
Future Development
Real estate properties
Number of Real Estate Properties	17
Area of real estate property \| ft²	10.8
Multifamily
Real estate properties
Number of Real Estate Properties	16
Number of Units in Real Estate Property \| item	6,318
Multifamily \| Asset under Construction
Real estate properties
Number of Real Estate Properties	2
Number of Units in Real Estate Property \| item	1,583
Commercial Real Estate
Real estate properties
Number of Real Estate Properties	26
Area of real estate property \| ft²	8.3
One Commercial Building
Real estate properties
Number of Real Estate Properties \| building	1
Subordinated interest	10.00%
Four Commercial Buildings
Real estate properties
Number of Real Estate Properties \| building	4
Subordinated interest	33.50%
Three Commercial Buildings
Real estate properties
Number of Real Estate Properties \| building	3
Wholly Owned Properties
Real estate properties
Number of properties for ground lease	2
Wholly Owned Properties \| Future Development
Real estate properties
Area of real estate property \| ft²	8.8
Wholly Owned Properties \| Multifamily
Real estate properties
Number of Units in Real Estate Property \| item	6,318
Wholly Owned Properties \| Multifamily \| Asset under Construction
Real estate properties
Number of Units in Real Estate Property \| item	1,583
Wholly Owned Properties \| Commercial Real Estate
Real estate properties
Area of real estate property \| ft²	7.7
Virginia Tech
Real estate properties
Under-construction property value developed by Virginia Tech \| $	$ 1
JBG Smith, LP
Real estate properties
Ownership interest by parent	87.80%
Three Commercial Buildings \| Three Commercial Buildings
Real estate properties
Ownership interest by parent	49.00%
Foundry \| Foundry
Real estate properties
Ownership interest by parent	9.90%

Number of key demand drivers.

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- Definition

Percentage of operating portfolio in which the entity serves as the developer.

+ References

No definition available.

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- Definition

Percentage of subordinated interest held through an unconsolidated real estate venture.

+ References

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- Definition

Value of real estate property being developed by Virginia Tech.

+ References

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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- Definition

Number of separate real estate development properties located on land subject to ground leases.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-3

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

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The number of units in a real estate property owned as of the balance sheet date.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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