Reportable Segments

3 Months Ended

Mar. 31, 2013

Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]

Segment Reporting Disclosure [Text Block]

Reportable Segments

Operating segments are defined as components of an enterprise that engage in business activities from which they may earn revenues and incur expenses and about which discrete financial information is available that is evaluated regularly by the chief operating decision maker. The chief operating decision maker decides how resources are allocated and assesses performance on a recurring basis at least quarterly.

The Company’s primary business is the acquisition, development and management of multifamily residential properties, which includes the generation of rental and other related income through the leasing of apartment units to residents. The chief operating decision maker evaluates the Company's operating performance geographically by market and both on a same store and non-same store basis. The Company’s operating segments (geographic markets) have been aggregated into four reportable segments based upon the geographic region in which they are located.

The Company’s fee and asset management and development (including its partially owned properties) activities are other business activities that do not constitute an operating segment and as such, have been aggregated in the "Other" category in the tables presented below.

All revenues are from external customers and there is no customer who contributed 10% or more of the Company’s total revenues during the quarters ended March 31, 2013 and 2012, respectively.

The primary financial measure for the Company’s rental real estate segment is net operating income (“NOI”), which represents rental income less: 1) property and maintenance expense; 2) real estate taxes and insurance expense; and 3) property management expense (all as reflected in the accompanying consolidated statements of operations). The Company believes that NOI is helpful to investors as a supplemental measure of its operating performance because it is a direct measure of the actual operating results of the Company’s apartment communities. Current year NOI is compared to prior year NOI and current year budgeted NOI as a measure of financial performance. The following tables present NOI for each segment from our rental real estate specific to continuing operations for the quarters ended March 31, 2013 and 2012, respectively, as well as total assets and capital expenditures at March 31, 2013 (amounts in thousands):

	Quarter Ended March 31, 2013
	Northeast		Northwest		Southeast		Southwest		Other (3)			Total
Rental income:
Same store (1)	$	186,839	$	102,570	$	64,678	$	111,566	$	—		$	465,653
Non-same store/other (2) (3)	43,702		17,389		256		8,100		1,902			71,349
Total rental income	230,541		119,959		64,934		119,666		1,902			537,002
Operating expenses:
Same store (1)	69,299		35,427		24,533		37,197		—			166,456
Non-same store/other (2) (3)	14,060		6,667		104		3,397		7,535			31,763
Total operating expenses	83,359		42,094		24,637		40,594		7,535			198,219
NOI:
Same store (1)	117,540		67,143		40,145		74,369		—			299,197
Non-same store/other (2) (3)	29,642		10,722		152		4,703		(5,633		)	39,586
Total NOI	$	147,182	$	77,865	$	40,297	$	79,072	$	(5,633	)	$	338,783
Total assets	$	11,571,120	$	4,745,161	$	1,707,027	$	3,925,524	$	1,846,326		$	23,795,158
Capital expenditures	$	9,030	$	8,137	$	3,799	$	3,993	$	1,640		$	26,599

(1) Same store primarily includes all properties acquired or completed and stabilized prior to January 1, 2012, less properties subsequently sold, which represented 90,350 apartment units.

(2) Non-same store primarily includes properties acquired after January 1, 2012, plus any properties in lease-up and not stabilized as of January 1, 2012.

(3) Other includes development and other corporate operations.

	Quarter Ended March 31, 2012
	Northeast			Northwest		Southeast		Southwest		Other (3)			Total
Rental income:
Same store (1)	$	178,867		$	95,144	$	61,778	$	107,363	$	—		$	443,152
Non-same store/other (2) (3)	404			722		—		87		19			1,232
Total rental income	179,271			95,866		61,778		107,450		19			444,384
Operating expenses:
Same store (1)	66,752			34,662		24,064		36,289		—			161,767
Non-same store/other (2) (3)	907			381		—		22		5,654			6,964
Total operating expenses	67,659			35,043		24,064		36,311		5,654			168,731
NOI:
Same store (1)	112,115			60,482		37,714		71,074		—			281,385
Non-same store/other (2) (3)	(503		)	341		—		65		(5,635		)	(5,732		)
Total NOI	$	111,612		$	60,823	$	37,714	$	71,139	$	(5,635	)	$	275,653

(1) Same store primarily includes all properties acquired or completed and stabilized prior to January 1, 2012, less properties subsequently sold, which represented 90,350 apartment units.

(2) Non-same store primarily includes properties acquired after January 1, 2012, plus any properties in lease-up and not stabilized as of January 1, 2012.

(3) Other includes development and other corporate operations.

Note: Markets/Metro Areas included in the above geographic segments are as follows:

(a) Northeast – New England (excluding Boston), Boston, New York and Washington DC.

(b) Northwest – Denver, San Francisco, Seattle and Tacoma.

(c) Southeast – Atlanta, Jacksonville, Orlando and South Florida.

(d) Southwest – Inland Empire, Los Angeles, Orange County, Phoenix and San Diego.

The following table presents a reconciliation of NOI from our rental real estate specific to continuing operations for the quarters ended March 31, 2013 and 2012, respectively (amounts in thousands):

	Quarter Ended March 31,
	2013			2012
Rental income	$	537,002		$	444,384
Property and maintenance expense	(107,083		)	(92,952		)
Real estate taxes and insurance expense	(68,647		)	(52,440		)
Property management expense	(22,489		)	(23,339		)
Total operating expenses	(198,219		)	(168,731		)
Net operating income	$	338,783		$	275,653