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

No definition available.

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Namespace Prefix:	jbgs_
Data Type:	xbrli:sharesItemType
Balance Type:	na
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

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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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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

The cash outflow during the period for redemption of redeemable noncontrolling interests.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB TOPIC 4.F)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770

+ Details

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Balance Type:	na
Period Type:	instant

- Details

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- Details

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- Details

Name:	srt_OwnershipAxis=jbgs_JBGSmithLPMember
Namespace Prefix:
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- Details

Name:	srt_OwnershipAxis=jbgs_ConsolidatedRealEstateVentureMember
Namespace Prefix:
Data Type:	na
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Redeemable Noncontrolling Interests - Narrative (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Feb. 21, 2023	Oct. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Noncontrolling Interest [Line Items]
Payments for redemption of interest			$ 9,531
OP Units
Noncontrolling Interest [Line Items]
Conversion of common limited partnership units to common shares			701,222	906,126
Subsequent Event \| OP Units
Noncontrolling Interest [Line Items]
Conversion of common limited partnership units to common shares	716,905
JBG Smith, LP
Noncontrolling Interest [Line Items]
Ownership interest by parent			88.30%
JBG Smith, LP \| OP Units
Noncontrolling Interest [Line Items]
Units outstanding			15,000,000.0
Ownership interest by parent			11.70%
Consolidated Real Estate Venture
Noncontrolling Interest [Line Items]
Ownership interest by parent			99.70%
Interest redeemed		3.70%
Payments for redemption of interest		$ 9,500