Organization, Basis of Presentation and Significant Accounting Policies (Details)	Mar. 31, 2017 state community home
Organization and Basis of Presentation
Number of operating apartment communities | community	260
Number of apartment homes included in operating apartment communities owned | home	74,952
Number of states where operating apartment communities owned are located | state	10
Number of communities with apartments under reconstruction | community	9
Number of apartment homes under reconstruction | home	4,075
Number of owned communities under construction | community	24
Expected number of apartment homes under construction | home	7,581
Communities under development rights | community	28
Estimated number of apartment homes in communities to be developed | home	9,304