Segment Reporting (Tables)

12 Months Ended

Dec. 31, 2010

Segment Reporting (Tables) [Abstract]

Summary of information for reportable segments

											Property		Net		Real Estate
	Rental		Resident Fees		Interest		Other		Total		Operating		Operating		Depreciation/		Interest		Total
	Income		and Services		Income		Income		Revenues		Expenses		Income(1)		Amortization		Expense		Assets
Year Ended December 31, 2010
Senior housing and care(2)	$	382,904	$	51,006	$	36,176	$	3,386	$	473,472	$	32,621	$	440,851	$	126,717	$	22,905	$	5,837,312
Medical facilities(3)		220,506		—		4,679		985		226,170		53,844		172,326		75,826		24,926		3,389,441
Non-segment/Corporate		—		—		—		2,874		2,874		—		2,874		—		113,129		224,981
	$	603,410	$	51,006	$	40,855	$	7,245	$	702,516	$	86,465	$	616,051	$	202,543	$	160,960	$	9,451,734
Year Ended December 31, 2009
Senior housing and care(2)	$	358,109	$	—	$	35,945	$	5,309	$	399,363	$	—	$	399,363	$	101,300	$	12,622	$	4,135,065
Medical facilities		181,802		—		4,940		9,368		196,110		48,965		147,145		63,623		20,584		2,140,044
Non-segment/Corporate		—		—		—		1,170		1,170		—		1,170		—		76,566		92,077
	$	539,911	$	—	$	40,885	$	15,847	$	596,643	$	48,965	$	547,678	$	164,923	$	109,772	$	6,367,186
Year Ended December 31, 2008
Senior housing and care(2)	$	345,053	$	—	$	35,143	$	5,994	$	386,190	$	—	$	386,190	$	98,675	$	7,176
Medical facilities		177,128		—		4,920		2,835		184,883		46,629		138,254		64,370		21,828
Non-segment/Corporate		—		—		—		1,692		1,692		—		1,692		—		112,055
	$	522,181	$	—	$	40,063	$	10,521	$	572,765	$	46,629	$	526,136	$	163,045	$	141,059

(1)	Net operating income (“NOI”) is used to evaluate the operating performance of our properties. We define NOI as total revenues, including tenant reimbursements, less property level operating expenses, which exclude depreciation and amortization, general and administrative expenses, impairments and interest expense. We believe NOI provides investors relevant and useful information because it measures the operating performance of our properties at the property level on an unleveraged basis. We use NOI to make decisions about resource allocations and to assess the property level performance of our properties.
(2)	Includes senior housing triple-net and senior housing operating results.
(3)	Excludes income and expense amounts related to our life science buildings held in an unconsolidated joint venture. Please see Note 7 for additional information.