Redeemable Noncontrolling Interests - Narrative (Details) - shares	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
OP Units
Redeemable Noncontrolling Interests
Redemption of common limited partnership units to common shares	647,387	468,081
JBG Smith, LP
Redeemable Noncontrolling Interests
Ownership interest by parent	84.00%
JBG Smith, LP \| OP Units
Redeemable Noncontrolling Interests
Units outstanding	13,900,000
Ownership interest by parent	16.00%

Common Shares Issued During Period in Connection with Redemption of OP Units

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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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- 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

The number of units or equivalent units outstanding for all classes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-5

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