Subsequent Events	6 Months Ended
Jun. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Pursuant to the Subsequent Events Topic of the Financial Accounting Standards Board ASC, we have evaluated subsequent events and transactions that occurred after our June 30, 2017 unaudited condensed combined balance sheet date for potential recognition or disclosure in our condensed combined financial statements and have also included such events in the footnotes herein. The Separation On July 17, 2017, we completed the Separation from Vornado. The Separation was effectuated by the distribution by Vornado of one common share of JBG SMITH for every two common shares of Vornado, and the distribution by VRLP of one common limited partnership unit of JBG SMITH LP for every two common limited partnership units of VRLP. A total of 94.7 million of our common shares and 5.8 million common limited partnership units of JBG SMITH LP were distributed to parties other than JBG SMITH. We are now an independent public company trading under the ticker symbol “JBGS” on the New York Stock Exchange. See Note 1 for further discussion. The Combination On July 18, 2017, we completed the Combination and acquired the management business and certain assets and liabilities, including mortgages payable with an aggregate principal balance of approximately $770.0 million, of The JBG Companies in exchange for 37.2 million common shares and common limited partnership units with a volume weighted average price on July 18, 2017 of $37.10 per share/unit. In accordance with ASC 805, Business Combinations, the Combination will be accounted for at fair value under the acquisition method of accounting. The purchase price allocation is in process and will be finalized after our valuation studies are complete. In addition, due to the short period of time between the closing of the Combination and the filing of this Quarterly Report on Form 10-Q, pro forma disclosures are not included and will be subsequently filed in an amended Current Report on Form 8-K, in accordance with SEC regulations. The JBG assets acquired comprise: (i) 30 operating assets comprising 19 office assets totaling approximately 3.6 million square feet (2.3 million square feet at our share), nine multifamily assets with 2,883 units (1,099 units at our share) and two other assets totaling approximately 490,000 square feet (73,000 square feet at our share); (ii) 11 office and multifamily assets under construction totaling over 2.5 million square feet (2.2 million square feet at our share); (iii) two near-term development office and multifamily assets totaling approximately 401,000 square feet (242,000 square feet at our share); (iv) 26 future development assets totaling approximately 11.7 million square feet (8.5 million square feet at our share) of estimated potential development density; and (v) JBG/Operating Partners, L.P., a real estate services company providing investment, development, asset management, property management, leasing, construction management and other services. JBG/Operating Partners, L.P. was owned by 20 unrelated individuals of which 19 became our employees, and three of these former owners serve on our Board of Trustees. Acquisition-related transaction costs and costs to effect the Separation and the Combination (such as advisory, legal, accounting, valuation and other professional fees) will not be included as a component of acquisition consideration. Such costs are expensed in the periods incurred. In connection with the Separation and the Combination, we entered into an agreement with Vornado under which Vornado will provide operational support for an initial period of up to two years. These services include information technology, financial reporting and payroll services. The charges for these services will be based on an hourly or per transaction fee arrangement including reimbursement for overhead and out-of-pocket expenses. Pursuant to an agreement, we are providing Vornado with leasing and property management services for certain of its assets held under joint venture arrangements that were not part of the Separation. We believe that the terms of both of these agreements are comparable to those that would have been negotiated on an arm’s-length basis. Other Events JBG SMITH 2017 Omnibus Share Plan On June 23, 2017, our Board of Trustees adopted the JBG SMITH 2017 Omnibus Share Plan (the “Plan”), effective as of July 17, 2017, and authorized the reservation of approximately 10.3 million of our common shares pursuant to the Plan. On July 10, 2017, our sole shareholder approved the Plan. Initial Formation Awards Pursuant to the Plan, on July 18, 2017, we granted approximately 2.7 million initial formation awards based on an aggregate notional value of approximately $100.0 million divided by the volume-weighted average price on July 18, 2017 of $37.10 per common share. The initial formation awards are structured in the form of profits interests that provide for a share of appreciation determined by the increase in the value of a common share at the time of conversion over the $37.10 volume-weighted average price of a common share at the time the formation unit was granted. The initial formation awards, subject to certain conditions, will vest 25% on each of the third and fourth anniversaries, and 50% on the fifth anniversary, of the closing of the Combination, subject to continued employment with JBG SMITH through each vesting date. 2017 Equity Grants On July 18, 2017, we granted long-term incentive partnership units (“LTIP Units”) to the seven independent Trustees in the amount of $250,000 each. The LTIP Units fully vested on the date of grant, but may not be sold while an independent Trustee is serving on the Board. On August 1, 2017, we granted approximately 303,700 LTIP Units to management and other employees under our Plan. The LTIP units vest in four equal installments on July 18 of each year, subject to continued employment. On August 1, 2017, we granted approximately 607,000 out-performance award units (“OPP Units”) to management and other employees under the Plan. OPP Units are part of a performance-based equity compensation plan pursuant to which participants have the opportunity to earn OPP units based on the relative performance of the total shareholder return (“TSR”) of our common shares compared to the companies in the FTSE NAREIT Equity Office Index, over the three-year performance period beginning on the August 1, 2017 grant date, inclusive of dividends and stock price appreciation. 50% of any OPP Units that are earned vest at the end of the three-year performance period and the remaining 50% on the fourth anniversary of the date of grant, subject to continued employment. Credit Facility On July 18, 2017, we entered into a $1.4 billion credit facility, consisting of a $1.0 billion revolving credit facility with a four-year term, with two six-month extension options, a five and a half-year delayed draw $200.0 million unsecured term loan (“Tranche A-1 Term Loan”) and a seven-year delayed draw $200.0 million unsecured term loan (“Tranche A-2 Term Loan”). The interest rate for the credit facility will vary based on a ratio of our total outstanding indebtedness to a valuation of certain real property businesses and assets and will range (a) in the case of the revolving credit facility, from LIBOR plus 1.10% to LIBOR plus 1.50%, (b) in the case of the Tranche A-1 Term Loan, from LIBOR plus 1.20% to LIBOR plus 1.70% and (c) in the case of the Tranche A-2 Term Loan, from LIBOR plus 1.55% to LIBOR plus 2.35%. On July 18, 2017, in connection with the Combination, we drew $115.8 million on the revolving credit facility and $50.0 million under the Tranche A-2 Term Loan. In connection with the execution of the credit facility, we incurred $6.8 million in fees and expenses.

Subsequent Events

Pursuant to the Subsequent Events Topic of the Financial Accounting Standards Board ASC, we have evaluated subsequent events and transactions that occurred after our June 30, 2017 unaudited condensed combined balance sheet date for potential recognition or disclosure in our condensed combined financial statements and have also included such events in the footnotes herein.

The Separation

On July 17, 2017, we completed the Separation from Vornado. The Separation was effectuated by the distribution by Vornado of one common share of JBG SMITH for every two common shares of Vornado, and the distribution by VRLP of one common limited partnership unit of JBG SMITH LP for every two common limited partnership units of VRLP. A total of 94.7 million of our common shares and 5.8 million common limited partnership units of JBG SMITH LP were distributed to parties other than JBG SMITH. We are now an independent public company trading under the ticker symbol “JBGS” on the New York Stock Exchange. See Note 1 for further discussion.

The Combination

On July 18, 2017, we completed the Combination and acquired the management business and certain assets and liabilities, including mortgages payable with an aggregate principal balance of approximately $770.0 million, of The JBG Companies in exchange for 37.2 million common shares and common limited partnership units with a volume weighted average price on July 18, 2017 of $37.10 per share/unit. In accordance with ASC 805, Business Combinations, the Combination will be accounted for at fair value under the acquisition method of accounting. The purchase price allocation is in process and will be finalized after our valuation studies are complete. In addition, due to the short period of time between the closing of the Combination and the filing of this Quarterly Report on Form 10-Q, pro forma disclosures are not included and will be subsequently filed in an amended Current Report on Form 8-K, in accordance with SEC regulations.

The JBG assets acquired comprise: (i) 30 operating assets comprising 19 office assets totaling approximately 3.6 million square feet (2.3 million square feet at our share), nine multifamily assets with 2,883 units (1,099 units at our share) and two other assets totaling approximately 490,000 square feet (73,000 square feet at our share); (ii) 11 office and multifamily assets under construction totaling over 2.5 million square feet (2.2 million square feet at our share); (iii) two near-term development office and multifamily assets totaling approximately 401,000 square feet (242,000 square feet at our share); (iv) 26 future development assets totaling approximately 11.7 million square feet (8.5 million square feet at our share) of estimated potential development density; and (v) JBG/Operating Partners, L.P., a real estate services company providing investment, development, asset management, property management, leasing, construction management and other services. JBG/Operating Partners, L.P. was owned by 20 unrelated individuals of which 19 became our employees, and three of these former owners serve on our Board of Trustees.

Acquisition-related transaction costs and costs to effect the Separation and the Combination (such as advisory, legal, accounting, valuation and other professional fees) will not be included as a component of acquisition consideration. Such costs are expensed in the periods incurred.

In connection with the Separation and the Combination, we entered into an agreement with Vornado under which Vornado will provide operational support for an initial period of up to two years. These services include information technology, financial reporting and payroll services. The charges for these services will be based on an hourly or per transaction fee arrangement including reimbursement for overhead and out-of-pocket expenses. Pursuant to an agreement, we are providing Vornado with leasing and property management services for certain of its assets held under joint venture arrangements that were not part of the Separation. We believe that the terms of both of these agreements are comparable to those that would have been negotiated on an arm’s-length basis.

Other Events

JBG SMITH 2017 Omnibus Share Plan

On June 23, 2017, our Board of Trustees adopted the JBG SMITH 2017 Omnibus Share Plan (the “Plan”), effective as of July 17, 2017, and authorized the reservation of approximately 10.3 million of our common shares pursuant to the Plan. On July 10, 2017, our sole shareholder approved the Plan.

Initial Formation Awards

Pursuant to the Plan, on July 18, 2017, we granted approximately 2.7 million initial formation awards based on an aggregate notional value of approximately $100.0 million divided by the volume-weighted average price on July 18, 2017 of $37.10 per common share. The initial formation awards are structured in the form of profits interests that provide for a share of appreciation determined by the increase in the value of a common share at the time of conversion over the $37.10 volume-weighted average price of a common share at the time the formation unit was granted. The initial formation awards, subject to certain conditions, will vest 25% on each of the third and fourth anniversaries, and 50% on the fifth anniversary, of the closing of the Combination, subject to continued employment with JBG SMITH through each vesting date.

2017 Equity Grants

On July 18, 2017, we granted long-term incentive partnership units (“LTIP Units”) to the seven independent Trustees in the amount of $250,000 each. The LTIP Units fully vested on the date of grant, but may not be sold while an independent Trustee is serving on the Board.

On August 1, 2017, we granted approximately 303,700 LTIP Units to management and other employees under our Plan. The LTIP units vest in four equal installments on July 18 of each year, subject to continued employment.

On August 1, 2017, we granted approximately 607,000 out-performance award units (“OPP Units”) to management and other employees under the Plan. OPP Units are part of a performance-based equity compensation plan pursuant to which participants have the opportunity to earn OPP units based on the relative performance of the total shareholder return (“TSR”) of our common shares compared to the companies in the FTSE NAREIT Equity Office Index, over the three-year performance period beginning on the August 1, 2017 grant date, inclusive of dividends and stock price appreciation. 50% of any OPP Units that are earned vest at the end of the three-year performance period and the remaining 50% on the fourth anniversary of the date of grant, subject to continued employment.

Credit Facility

On July 18, 2017, we entered into a $1.4 billion credit facility, consisting of a $1.0 billion revolving credit facility with a four-year term, with two six-month extension options, a five and a half-year delayed draw $200.0 million unsecured term loan (“Tranche A-1 Term Loan”) and a seven-year delayed draw $200.0 million unsecured term loan (“Tranche A-2 Term Loan”). The interest rate for the credit facility will vary based on a ratio of our total outstanding indebtedness to a valuation of certain real property businesses and assets and will range (a) in the case of the revolving credit facility, from LIBOR plus 1.10% to LIBOR plus 1.50%, (b) in the case of the Tranche A-1 Term Loan, from LIBOR plus 1.20% to LIBOR plus 1.70% and (c) in the case of the Tranche A-2 Term Loan, from LIBOR plus 1.55% to LIBOR plus 2.35%. On July 18, 2017, in connection with the Combination, we drew $115.8 million on the revolving credit facility and $50.0 million under the Tranche A-2 Term Loan. In connection with the execution of the credit facility, we incurred $6.8 million in fees and expenses.