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

No definition available.

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Period Type:	duration

- Definition

The percentage of entity's interest in net assets of the subsidiary redeemed expressed as a percentage

+ References

No definition available.

+ Details

Name:	jbgs_NoncontrollingInterestOwnershipPercentageRedeemed
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Period Type:	duration

- 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.

+ Details

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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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

+ Details

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Balance Type:	na
Period Type:	instant

- Details

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- Details

Name:	srt_OwnershipAxis=jbgs_JBGSmithLPMember
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- Details

Name:	srt_OwnershipAxis=jbgs_ConsolidatedRealEstateVentureMember
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Redeemable Noncontrolling Interests - Narrative (Details) - shares shares in Millions	1 Months Ended	12 Months Ended
	Feb. 28, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
OP Units
Redeemable Noncontrolling Interests
Redemption of common limited partnership units to common shares		1.0	2.8
JBG Smith, LP
Redeemable Noncontrolling Interests
Ownership interest by parent		86.00%
JBG Smith, LP \| OP Units
Redeemable Noncontrolling Interests
Units outstanding		13.8
Ownership interest by parent		14.00%
Consolidated Real Estate Venture
Redeemable Noncontrolling Interests
Ownership interest by parent		100.00%		99.70%
Interest redeemed	0.30%