Redeemable Noncontrolling Interests - Summary of the Activity of Redeemable Noncontrolling Interests (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Temporary Equity
Beginning Balance	$ 558,140	$ 609,129
Fair value of OP Unit redemptions	(57,318)	(109,208)	$ 0
LTIP Units issued in lieu of cash bonuses (1)	3,954	0
Net income (loss) attributable to redeemable noncontrolling interests	8,573	6,710
Other comprehensive income	(2,584)	1,384
Temporary Equity, Contributions (Distributions)	(15,254)	(18,237)
Share-based compensation expense	63,264	52,190
Adjustment to redemption value	53,983	16,172
Ending Balance	612,758	558,140	609,129
JBG Smith, LP
Temporary Equity
Beginning Balance	552,159	603,717
Fair value of OP Unit redemptions	(57,318)	(109,208)
LTIP Units issued in lieu of cash bonuses (1)	3,954	0
Net income (loss) attributable to redeemable noncontrolling interests	8,566	6,641
Other comprehensive income	(2,584)	1,384
Temporary Equity, Contributions (Distributions)	(15,325)	(18,737)
Share-based compensation expense	63,264	52,190
Adjustment to redemption value	53,983	16,172
Ending Balance	606,699	552,159	603,717
Consolidated Real Estate Venture
Temporary Equity
Beginning Balance	5,981	5,412
Fair value of OP Unit redemptions	0	0
LTIP Units issued in lieu of cash bonuses (1)	0	0
Net income (loss) attributable to redeemable noncontrolling interests	7	69
Other comprehensive income	0	0
Temporary Equity, Contributions (Distributions)	71	500
Share-based compensation expense	0	0
Adjustment to redemption value	0	0
Ending Balance	$ 6,059	$ 5,981	$ 5,412

Temporary Equity, Contributions (Distributions)

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- Definition

Temporary Equity, Other Comprehensive Income (Loss)

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Temporary Equity, Redemptions of OP Units

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Temporary Equity, Share-based Compensation

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (16)(c)
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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Value of stock issued in lieu of cash for services contributed to the entity. Value of the stock issued includes, but is not limited to, services contributed by vendors and founders.

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- Definition

Change in the value of each type or class of stock classified as temporary equity during the period. The redemption requirement does not constitute an unconditional obligation that will be settled in a variable number of shares constituting a monetary value predominantly indexed to (a) a fixed monetary amount known at inception, (b) an amount inversely correlated with the residual value of the entity, or (c) an amount determined by reference to something other than the fair value of issuer's stock. Does not include mandatorily redeemable stock. The exception is if redemption is required upon liquidation or termination of the reporting entity.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

The portion of net income or loss attributable to temporary equity interest.

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