Subsequent Events	12 Months Ended
Dec. 31, 2014
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events The Company has evaluated subsequent events through the date on which this Form 10-K was filed, the date on which these financial statements were issued, and identified the items below for discussion. In January 2015: The Company sold Avalon on Stamford Harbor, located in Stamford, CT. Avalon on Stamford Harbor contains 323 homes and a working marina containing 74 boat slips and was sold for $115,500,000. The Company acquired land for $325,000,000 associated with three Development Rights located in New York, NY and Bellevue, WA. If developed as expected, the development rights related to this land will contain 910 apartment homes for a projected total capital cost of $509,717,000. A fire occurred at the Company's Avalon at Edgewater apartment community located in Edgewater, New Jersey ("Edgewater"). Edgewater consisted of two residential buildings. One building, which contained 240 apartment homes, was destroyed and is uninhabitable. The second building, which contains 168 apartment homes, has been reoccupied and the Company currently believes it only suffered minimal damage. The Company is currently assessing its direct losses resulting from the fire, which could vary based on costs and time to rebuild, as well its liability to third parties who incurred damages on account of the fire. To date, a number of lawsuits on behalf of former residents have been filed against the Company, including three purported class actions. While the Company currently believes that its direct losses and its liability to third parties will be substantially covered by its insurance policies, including coverage for the replacement cost of the building, third party claims, and business interruption loss, subject to deductibles as well as a self-insured portion of the property insurance for which the Company is obligated for 12% of the first $50,000,000 in losses, the Company can give no assurances in this regard and continues to evaluate this matter. As of December 31, 2014, Edgewater was encumbered with a fixed-rate secured mortgage note with an effective interest rate of 5.95%, and an outstanding principal balance of $75,012,000, due in May 2019 (the “Edgewater Mortgage”). The Edgewater Mortgage stipulates that in the event of a casualty loss such as the Edgewater fire, the lender has absolute discretion to determine the disposition of the insurance proceeds, and can compel the Company (i) to direct the insurance proceeds to be used for the restoration of Edgewater, or (ii) to apply the insurance proceeds to repay the outstanding loan balance, at par. As of the date of this Form 10-K, the Company is complying with all lender requirements and continues to work with the lender to resolve open issues related to the Edgewater Mortgage. The Company received $20,700,000 from the joint venture partner associated with MVP I, LLC, the entity that owns Avalon at Mission Bay North II, upon agreement with the partner to modify the joint venture agreement to eliminate the Company's promoted interest for future return calculations and associated distributions. Prospectively, earnings and distributions will be based on the Company's 25.0% equity interest in the venture.

Subsequent Events

The Company has evaluated subsequent events through the date on which this Form 10-K was filed, the date on which these financial statements were issued, and identified the items below for discussion.

In January 2015:

The Company sold Avalon on Stamford Harbor, located in Stamford, CT. Avalon on Stamford Harbor contains 323 homes and a working marina containing 74 boat slips and was sold for $115,500,000.

The Company acquired land for $325,000,000 associated with three Development Rights located in New York, NY and Bellevue, WA. If developed as expected, the development rights related to this land will contain 910 apartment homes for a projected total capital cost of $509,717,000.

A fire occurred at the Company's Avalon at Edgewater apartment community located in Edgewater, New Jersey ("Edgewater"). Edgewater consisted of two residential buildings. One building, which contained 240 apartment homes, was destroyed and is uninhabitable. The second building, which contains 168 apartment homes, has been reoccupied and the Company currently believes it only suffered minimal damage. The Company is currently assessing its direct losses resulting from the fire, which could vary based on costs and time to rebuild, as well its liability to third parties who incurred damages on account of the fire. To date, a number of lawsuits on behalf of former residents have been filed against the Company, including three purported class actions. While the Company currently believes that its direct losses and its liability to third parties will be substantially covered by its insurance policies, including coverage for the replacement cost of the building, third party claims, and business interruption loss, subject to deductibles as well as a self-insured portion of the property insurance for which the Company is obligated for 12% of the first $50,000,000 in losses, the Company can give no assurances in this regard and continues to evaluate this matter. As of December 31, 2014, Edgewater was encumbered with a fixed-rate secured mortgage note with an effective interest rate of 5.95%, and an outstanding principal balance of $75,012,000, due in May 2019 (the “Edgewater Mortgage”). The Edgewater Mortgage stipulates that in the event of a casualty loss such as the Edgewater fire, the lender has absolute discretion to determine the disposition of the insurance proceeds, and can compel the Company (i) to direct the insurance proceeds to be used for the restoration of Edgewater, or (ii) to apply the insurance proceeds to repay the outstanding loan balance, at par. As of the date of this Form 10-K, the Company is complying with all lender requirements and continues to work with the lender to resolve open issues related to the Edgewater Mortgage.

The Company received $20,700,000 from the joint venture partner associated with MVP I, LLC, the entity that owns Avalon at Mission Bay North II, upon agreement with the partner to modify the joint venture agreement to eliminate the Company's promoted interest for future return calculations and associated distributions. Prospectively, earnings and distributions will be based on the Company's 25.0% equity interest in the venture.