Basis of Presentation and Summary of Significant Accounting Policies - Revenue Recognition (Details)	12 Months Ended
Dec. 31, 2014
Revenue Recognition [Abstract]
Average Term of Operating Leases with Apartment Residents	12 months

Term of the lessor's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_LessorLeasingArrangementsOperatingLeasesTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration