Related Party Transactions	12 Months Ended
Dec. 31, 2017
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The Company has adopted written related party transaction guidelines that are intended to cover transactions in which the Company (including entities it controls) is a party and in which any “related person” has a direct or indirect interest. A “related person” means any person who is or was (since the beginning of the last fiscal year) a Company director, director nominee, or executive officer, any beneficial owner of more than 5% of the Company’s outstanding common stock, and any immediate family member of any of the foregoing persons. A related person may be considered to have an indirect interest in a transaction if he or she (i) is an owner, director, officer or employee of or otherwise associated with another company that is engaging in a transaction with the Company, or (ii) otherwise, through one or more entities or arrangements, has an indirect financial interest in or personal benefit from the transaction. The related person transaction review and approval process is intended to determine, among any other relevant issues, the dollar amount involved in the transaction; the nature and value of any related person’s direct or indirect interest (if any) in the transaction; and whether or not (i) a related person’s interest is material, (ii) the transaction is fair, reasonable, and serves the best interest of the Company and its shareholders, and (iii) whether the transaction or relationship should be entered into, continued or ended. The Company’s Chairman and founder, Mr. George 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. MMI is a national brokerage firm listed on the NYSE that underwent its initial public offering in 2013. For the year ended December 31, 2016, the Company paid brokerage commissions totaling $1.1 million to affiliates of MMC related to real estate transactions. There were no brokerage commissions paid by the Company to MMI or its affiliates during 2017 and 2015. The Company charges certain fees relating to its co-investments for asset management, property management, development and redevelopment services. These fees from affiliates total $12.6 million, $12.4 million, and $15.6 million for the years ended December 31, 2017, 2016 and 2015, respectively. All of these fees are net of intercompany amounts eliminated by the Company. The Company netted development and redevelopment fees of $3.0 million, $4.2 million, and $6.7 million against general and administrative expenses for the years ended December 31, 2017, 2016 and 2015, respectively. As described in Note 4, the Company has provided short-term bridge loans to affiliates. As of December 31, 2017 and 2016, $5.1 million and $4.7 million, respectively, of short-term loans remained outstanding due from joint venture affiliates and are classified within notes and other receivables in the accompanying 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 had an outstanding balance of $6.7 million and $6.6 million, as of December 31, 2017 and 2016, respectively, and is classified within notes and other receivables in the accompanying consolidated balance sheets. 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 limited partnership 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 consolidation analysis performed by the Company. In August 2017, the Company provided a $55.0 million related party bridge loan to a property acquired by Wesco V, LLC. The note receivable accrued interest at 3.5% and was paid off in November 2017. In November 2017, the Company provided a $29.5 million related party bridge loan to a property acquired by BEX III, LLC. The note receivable accrues interest at 3.5% and is scheduled to mature on March 9, 2018. The bridge loan is classified within notes and other receivables in the accompanying condensed consolidated balance sheets and had an outstanding balance of $29.5 million as of December 31, 2017. 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. In January 2013, the Company invested $8.6 million as a preferred equity interest investment in an entity affiliated with MMC that owns an apartment development in Redwood City, CA. In March 2015 the Company's preferred interest investment was prepaid and the Company recognized a gain of $0.5 million as a result of the prepayment. In 2010, an Executive Vice President of the Company invested $4.0 million for a 3% limited partnership interest in a partnership with the Company that owns Essex Skyline at MacArthur Place. The Executive Vice President’s investment is equal to a pro-rata share of the contributions to the limited partnership. The Executive Vice President’s investment also receives pro-rata distributions resulting from distributable cash generated by the property if and when distributions are made.

Related Party Transactions

The Company has adopted written related party transaction guidelines that are intended to cover transactions in which the Company (including entities it controls) is a party and in which any “related person” has a direct or indirect interest. A “related person” means any person who is or was (since the beginning of the last fiscal year) a Company director, director nominee, or executive officer, any beneficial owner of more than 5% of the Company’s outstanding common stock, and any immediate family member of any of the foregoing persons. A related person may be considered to have an indirect interest in a transaction if he or she (i) is an owner, director, officer or employee of or otherwise associated with another company that is engaging in a transaction with the Company, or (ii) otherwise, through one or more entities or arrangements, has an indirect financial interest in or personal benefit from the transaction.

The related person transaction review and approval process is intended to determine, among any other relevant issues, the dollar amount involved in the transaction; the nature and value of any related person’s direct or indirect interest (if any) in the transaction; and whether or not (i) a related person’s interest is material, (ii) the transaction is fair, reasonable, and serves the best interest of the Company and its shareholders, and (iii) whether the transaction or relationship should be entered into, continued or ended.

The Company’s Chairman and founder, Mr. George 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. MMI is a national brokerage firm listed on the NYSE that underwent its initial public offering in 2013. For the year ended December 31, 2016, the Company paid brokerage commissions totaling $1.1 million to affiliates of MMC related to real estate transactions. There were no brokerage commissions paid by the Company to MMI or its affiliates during 2017 and 2015.

The Company charges certain fees relating to its co-investments for asset management, property management, development and redevelopment services. These fees from affiliates total $12.6 million, $12.4 million, and $15.6 million for the years ended December 31, 2017, 2016 and 2015, respectively. All of these fees are net of intercompany amounts eliminated by the Company. The Company netted development and redevelopment fees of $3.0 million, $4.2 million, and $6.7 million against general and administrative expenses for the years ended December 31, 2017, 2016 and 2015, respectively.

As described in Note 4, the Company has provided short-term bridge loans to affiliates. As of December 31, 2017 and 2016, $5.1 million and $4.7 million, respectively, of short-term loans remained outstanding due from joint venture affiliates and are classified within notes and other receivables in the accompanying 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 had an outstanding balance of $6.7 million and $6.6 million, as of December 31, 2017 and 2016, respectively, and is classified within notes and other receivables in the accompanying consolidated balance sheets.

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 limited partnership 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 consolidation analysis performed by the Company.

In August 2017, the Company provided a $55.0 million related party bridge loan to a property acquired by Wesco V, LLC. The note receivable accrued interest at 3.5% and was paid off in November 2017.

In November 2017, the Company provided a $29.5 million related party bridge loan to a property acquired by BEX III, LLC. The note receivable accrues interest at 3.5% and is scheduled to mature on March 9, 2018. The bridge loan is classified within notes and other receivables in the accompanying condensed consolidated balance sheets and had an outstanding balance of $29.5 million as of December 31, 2017.

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.

In January 2013, the Company invested $8.6 million as a preferred equity interest investment in an entity affiliated with MMC that owns an apartment development in Redwood City, CA. In March 2015 the Company's preferred interest investment was prepaid and the Company recognized a gain of $0.5 million as a result of the prepayment.

In 2010, an Executive Vice President of the Company invested $4.0 million for a 3% limited partnership interest in a partnership with the Company that owns Essex Skyline at MacArthur Place. The Executive Vice President’s investment is equal to a pro-rata share of the contributions to the limited partnership. The Executive Vice President’s investment also receives pro-rata distributions resulting from distributable cash generated by the property if and when distributions are made.