Reportable Segments

12 Months Ended

Dec. 31, 2011

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 about which separate financial information is available that is evaluated regularly by senior management. Senior management decides how resources are allocated and assesses performance on a monthly basis.

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. Senior management evaluates the performance of each of our apartment communities individually and geographically, and both on a same store and non-same store basis; however, each of our apartment communities generally has similar economic characteristics, residents, products and services. The Company’s operating segments have been aggregated by geography in a manner identical to that which is provided to its chief operating decision maker.

The Company’s fee and asset management, development (including its partially owned properties) and condominium conversion activities are immaterial and do not individually meet the threshold requirements of a reportable segment and as such, have been aggregated in the “Other” segment 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 three years ended December 31, 2011, 2010 or 2009.

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 years ended December 31, 2011, 2010 and 2009, respectively, as well as total assets for the years ended December 31, 2011 and 2010, respectively (amounts in thousands):

	Year Ended December 31, 2011
	Northeast		Northwest		Southeast		Southwest		Other (3)			Total
Rental income:
Same store (1)	$	584,405	$	344,615	$	356,936	$	426,472	$	—		$	1,712,428
Non-same store/other (2) (3)	157,907		42,633		16,487		45,489		5,493			268,009
Properties sold – March YTD 2012 (4)	—		—		—		—		(20,194		)	(20,194		)
Total rental income	742,312		387,248		373,423		471,961		(14,701		)	1,960,243
Operating expenses:
Same store (1)	211,494		120,920		140,145		145,153		—			617,712
Non-same store/other (2) (3)	56,591		16,021		5,974		17,619		7,366			103,571
Properties sold – March YTD 2012 (4)	—		—		—		—		(7,174		)	(7,174		)
Total operating expenses	268,085		136,941		146,119		162,772		192			714,109
NOI:
Same store (1)	372,911		223,695		216,791		281,319		—			1,094,716
Non-same store/other (2) (3)	101,316		26,612		10,513		27,870		(1,873		)	164,438
Properties sold – March YTD 2012 (4)	—		—		—		—		(13,020		)	(13,020		)
Total NOI	$	474,227	$	250,307	$	227,304	$	309,189	$	(14,893	)	$	1,246,134
Total assets	$	6,539,328	$	2,885,791	$	2,506,330	$	3,385,517	$	1,342,337		$	16,659,303

(1) Same store primarily includes all properties acquired or completed and stabilized prior to January 1, 2010, less properties subsequently sold, which represented 101,312 apartment units.

(2) Non-same store primarily includes properties acquired after January 1, 2010, plus any properties in lease-up and not stabilized as of January 1, 2010.

(3) Other includes development, condominium conversion overhead of $0.4 million and other corporate operations.

(4) Properties sold – March YTD 2012 reflects discontinued operations for properties sold during the first three months of 2012.

	Year Ended December 31, 2010
	Northeast		Northwest		Southeast		Southwest		Other (3)			Total
Rental income:
Same store (1)	$	553,561	$	322,427	$	342,080	$	412,414	$	—		$	1,630,482
Non-same store/other (2) (3)	95,493		18,825		9,009		13,587		(3,604		)	133,310
Properties sold – March YTD 2012 (4)	—		—		—		—		(19,024		)	(19,024		)
Total rental income	649,054		341,252		351,089		426,001		(22,628		)	1,744,768
Operating expenses:
Same store (1)	207,131		119,797		139,550		147,732		—			614,210
Non-same store/other (2) (3)	48,119		8,300		3,729		7,198		12,230			79,576
Properties sold – March YTD 2012 (4)	—		—		—		—		(7,103		)	(7,103		)
Total operating expenses	255,250		128,097		143,279		154,930		5,127			686,683
NOI:
Same store (1)	346,430		202,630		202,530		264,682		—			1,016,272
Non-same store/other (2) (3)	47,374		10,525		5,280		6,389		(15,834		)	53,734
Properties sold – March YTD 2012 (4)	—		—		—		—		(11,921		)	(11,921		)
Total NOI	$	393,804	$	213,155	$	207,810	$	271,071	$	(27,755	)	$	1,058,085
Total assets	$	6,158,908	$	2,630,850	$	2,495,748	$	3,140,153	$	1,758,535		$	16,184,194

(1) Same store primarily includes all properties acquired or completed and stabilized prior to January 1, 2010, less properties subsequently sold, which represented 101,312 apartment units.

(2) Non-same store primarily includes properties acquired after January 1, 2010, plus any properties in lease-up and not stabilized as of January 1, 2010.

(3) Other includes development, condominium conversion overhead of $0.6 million and other corporate operations.

(4) Properties sold – March YTD 2012 reflects discontinued operations for properties sold during the first three months of 2012.

	Year Ended December 31, 2009
	Northeast		Northwest		Southeast		Southwest		Other (3)			Total
Rental income:
Same store (1)	$	566,518	$	357,502	$	383,239	$	423,076	$	—		$	1,730,335
Non-same store/other (2) (3)	23,195		2,010		4,268		16,985		69,364			115,822
Properties sold in 2011 (4)	—		—		—		—		(216,279		)	(216,279		)
Properties sold – March YTD 2012 (5)	—		—		—		—		(19,409		)	(19,409		)
Total rental income	589,713		359,512		387,507		440,061		(166,324		)	1,610,469
Operating expenses:
Same store (1)	211,352		129,696		158,977		148,483		—			648,508
Non-same store/other (2) (3)	12,798		1,851		1,727		9,418		68,692			94,486
Properties sold in 2011 (4)	—		—		—		—		(111,589		)	(111,589		)
Properties sold – March YTD 2012 (5)	—		—		—		—		(6,762		)	(6,762		)
Total operating expenses	224,150		131,547		160,704		157,901		(49,659		)	624,643
NOI:
Same store (1)	355,166		227,806		224,262		274,593		—			1,081,827
Non-same store/other (2) (3)	10,397		159		2,541		7,567		672			21,336
Properties sold in 2011 (4)	—		—		—		—		(104,690		)	(104,690		)
Properties sold – March YTD 2012 (5)	—		—		—		—		(12,647		)	(12,647		)
Total NOI	$	365,563	$	227,965	$	226,803	$	282,160	$	(116,665	)	$	985,826

(1) Same store primarily includes all properties acquired or completed and stabilized prior to January 1, 2009, less properties subsequently sold, which represented 112,042 apartment units.

(2) Non-same store primarily includes properties acquired after January 1, 2009, plus any properties in lease-up and not stabilized as of January 1, 2009.

(3) Other includes development, condominium conversion overhead of $1.4 million and other corporate operations.

(4) Reflects discontinued operations for properties sold during 2011.

(5) Properties sold – March YTD 2012 reflects discontinued operations for properties sold during the first three months of 2012.

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

(a) Northeast – New England (excluding Boston), Boston, New York Metro, DC Northern Virginia and Suburban Maryland.

(b) Northwest – Denver, San Francisco Bay Area and Seattle/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 years ended December 31, 2011, 2010 and 2009, respectively (amounts in thousands):

	Year Ended December 31,
	2011			2010			2009
Rental income	$	1,960,243		$	1,744,768		$	1,610,469
Property and maintenance expense	(412,233		)	(397,573		)	(365,448		)
Real estate taxes and insurance expense	(219,743		)	(209,023		)	(187,895		)
Property management expense	(82,133		)	(80,087		)	(71,300		)
Total operating expenses	(714,109		)	(686,683		)	(624,643		)
Net operating income	$	1,246,134		$	1,058,085		$	985,826