Participation threshold price per share.

No definition available.

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Namespace Prefix:	jbgs_
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Balance Type:	na
Period Type:	instant

- Definition

Percentage of increase or decrease in units earned.

+ References

No definition available.

+ Details

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Namespace Prefix:	jbgs_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The aggregate grant date fair value of the awards made under the stock-based compensation plan.

+ References

No definition available.

+ Details

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

- Definition

The number of vested equity-based payment instruments, excluding stock (or unit) options granted.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

+ Details

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

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Share-Based Payments and Employee Benefits - AO LTIP Units (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended				12 Months Ended
	Jan. 01, 2022	Feb. 22, 2022	Jan. 31, 2022	Jul. 31, 2021	Jan. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
AO LTIP Units \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Participation Threshold Share Price	$ 32.30
Vesting period	3 years
Vesting (as a percent)	50.00%
Percentage of (Increase) (Decrease) in Units Earned	25.00%
Grants in period (in shares)			1,500,000
Time-Based LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period						4 years
Vesting (as a percent)				50.00%
Grants in period (in shares)				608,325		498,955	381,504	351,982
Time-Based LTIP Units \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)			702,888
Performance LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period						3 years
Vesting (as a percent)				50.00%
Grants in period (in shares)				844,070		627,874	593,100	478,411
Fair value of awards on grant date						$ 29.0	$ 11.1	$ 9.3
Performance LTIP Units \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)			21,705
Time-Based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)					22,194	22,194
Time-Based RSUs \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)			39,536
LTIP Units [Member] \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of awards on grant date		$ 5.6
Fully vested grants (in shares)		252,206
2022 Grants \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of awards on grant date			$ 27.3