Redeemable Noncontrolling Interests - Narrative (Details) - shares	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Consolidated Real Estate Venture
Noncontrolling Interest [Line Items]
Ownership interest by parent, threshold for capital contributions to cease	97.00%
OP Units [Member]
Noncontrolling Interest [Line Items]
Conversion of common limited partnership units to common shares	280,451	648,752
JBG Smith, LP
Noncontrolling Interest [Line Items]
Ownership interest by parent	88.40%
JBG Smith, LP \| OP Units [Member]
Noncontrolling Interest [Line Items]
Units outstanding	15,300,000
Ownership interest by parent	11.60%
Consolidated Real Estate Venture
Noncontrolling Interest [Line Items]
Ownership interest by parent	96.00%

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Noncontrolling Interest, Capital Contribution Threshold, Ownership Percentage by Parent

+ References

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+ References

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

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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

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