Related Party Transactions	9 Months Ended
Sep. 30, 2018
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The Company charges certain fees relating to its co-investments for asset management, property management, development and redevelopment services. These fees from affiliates totaled $3.6 million and $3.1 million during the three months ended September 30, 2018 and 2017, respectively, and $10.0 million and $9.0 million during the nine months ended September 30, 2018 and 2017, respectively. All of these fees are net of intercompany amounts eliminated by the Company. The Company netted development and redevelopment fees of $1.3 million and $0.7 million against general and administrative expenses for the three months ended September 30, 2018 and 2017, respectively, and $3.2 million and $2.1 million for the nine months ended September 30, 2018 and 2017, respectively. In November 2017, the Company provided a $29.5 million related party bridge loan to a property acquired by BEX III. The note receivable accrued interest at 3.5% and was paid off in January 2018. The bridge loan was classified within notes and other receivables in the accompanying condensed consolidated balance sheets and had no amount outstanding as of September 30, 2018. The Company’s Chairman and founder, Mr. George M. Marcus, is the Chairman of the Marcus & Millichap Company (“MMC”), which is a parent company of a diversified group of real estate service, investment, and development firms. Mr. Marcus is also the Co-Chairman of Marcus & Millichap, Inc. (“MMI”), and Mr. Marcus owns a controlling interest in MMI, a national brokerage firm listed on the New York Stock Exchange. In October 2018, the Company funded a $18.6 million preferred equity investment in an entity whose sponsor is an affiliate of MMC. The entity wholly owns a 268 apartment home community development located in Burlingame, CA. This investment will accrue interest based on an initial 12.00% preferred return. The investment is scheduled to mature in April 2024. In May 2018, the Company made a commitment to fund a $26.5 million preferred equity investment in an entity whose sponsors include an affiliate of MMC. The entity wholly owns a 400 apartment home community located in Ventura, CA. This investment will accrue interest based on a 10.25% preferred return. The investment is scheduled to mature in May 2023. As of September 30, 2018, the Company had funded $20.6 million of the commitment. The remaining committed amount will be funded if and when requested by the sponsors. In March 2017, the Company converted its existing $15.3 million preferred equity investment in Sage at Cupertino, a 230 apartment home community located in San Jose, CA, into a 40.5% common equity ownership interest in the property. The Company issued DownREIT units to the other members, including an MMC affiliate, based on an estimated property valuation of $90.0 million. At the time of the conversion, the property was encumbered by $52.0 million of mortgage debt. As a result of this transaction, the Company consolidates the property, based on a VIE analysis performed by the Company. In 2015, the Company made preferred equity investments totaling $20.0 million in three entities affiliated with MMC that own apartment communities in California. The Company earns a 9.5% preferred return on each such investment. One $5.0 million investment, which was scheduled to mature in 2022, was fully redeemed in 2017. The remaining two investments are scheduled to mature in 2022. As described in Note 5, Notes and Other Receivables, the Company has provided short-term loans to affiliates. As of September 30, 2018 and December 31, 2017, $3.6 million and $5.1 million, respectively, of short-term loans remained outstanding due from joint venture affiliates and is classified within notes and other receivables in the accompanying condensed consolidated balance sheets. In November 2016, the Company provided a $6.6 million mezzanine loan to a limited liability company in which MMC holds a significant ownership interest through subsidiaries. The mezzanine loan is classified within notes and other receivables in the accompanying condensed consolidated balance sheets and had an outstanding balance of $6.6 million and $6.7 million as of September 30, 2018 and December 31, 2017, respectively.

Related Party Transactions

The Company charges certain fees relating to its co-investments for asset management, property management, development and redevelopment services. These fees from affiliates totaled $3.6 million and $3.1 million during the three months ended September 30, 2018 and 2017, respectively, and $10.0 million and $9.0 million during the nine months ended September 30, 2018 and 2017, respectively. All of these fees are net of intercompany amounts eliminated by the Company. The Company netted development and redevelopment fees of $1.3 million and $0.7 million against general and administrative expenses for the three months ended September 30, 2018 and 2017, respectively, and $3.2 million and $2.1 million for the nine months ended September 30, 2018 and 2017, respectively.

In November 2017, the Company provided a $29.5 million related party bridge loan to a property acquired by BEX III. The note receivable accrued interest at 3.5% and was paid off in January 2018. The bridge loan was classified within notes and other receivables in the accompanying condensed consolidated balance sheets and had no amount outstanding as of September 30, 2018.

The Company’s Chairman and founder, Mr. George M. Marcus, is the Chairman of the Marcus & Millichap Company (“MMC”), which is a parent company of a diversified group of real estate service, investment, and development firms. Mr. Marcus is also the Co-Chairman of Marcus & Millichap, Inc. (“MMI”), and Mr. Marcus owns a controlling interest in MMI, a national brokerage firm listed on the New York Stock Exchange.

In October 2018, the Company funded a $18.6 million preferred equity investment in an entity whose sponsor is an affiliate of MMC. The entity wholly owns a 268 apartment home community development located in Burlingame, CA. This investment will accrue interest based on an initial 12.00% preferred return. The investment is scheduled to mature in April 2024.

In May 2018, the Company made a commitment to fund a $26.5 million preferred equity investment in an entity whose sponsors include an affiliate of MMC. The entity wholly owns a 400 apartment home community located in Ventura, CA. This investment will accrue interest based on a 10.25% preferred return. The investment is scheduled to mature in May 2023. As of September 30, 2018, the Company had funded $20.6 million of the commitment. The remaining committed amount will be funded if and when requested by the sponsors.

In March 2017, the Company converted its existing $15.3 million preferred equity investment in Sage at Cupertino, a 230 apartment home community located in San Jose, CA, into a 40.5% common equity ownership interest in the property. The Company issued DownREIT units to the other members, including an MMC affiliate, based on an estimated property valuation of $90.0 million. At the time of the conversion, the property was encumbered by $52.0 million of mortgage debt. As a result of this transaction, the Company consolidates the property, based on a VIE analysis performed by the Company.

In 2015, the Company made preferred equity investments totaling $20.0 million in three entities affiliated with MMC that own apartment communities in California. The Company earns a 9.5% preferred return on each such investment. One $5.0 million investment, which was scheduled to mature in 2022, was fully redeemed in 2017. The remaining two investments are scheduled to mature in 2022.

As described in Note 5, Notes and Other Receivables, the Company has provided short-term loans to affiliates. As of September 30, 2018 and December 31, 2017, $3.6 million and $5.1 million, respectively, of short-term loans remained outstanding due from joint venture affiliates and is classified within notes and other receivables in the accompanying condensed consolidated balance sheets. In November 2016, the Company provided a $6.6 million mezzanine loan to a limited liability company in which MMC holds a significant ownership interest through subsidiaries. The mezzanine loan is classified within notes and other receivables in the accompanying condensed consolidated balance sheets and had an outstanding balance of $6.6 million and $6.7 million as of September 30, 2018 and December 31, 2017, respectively.