CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Rental income:
Triple-net leased	$ 831,221	$ 637,294	$ 453,592
Medical office buildings	362,839	166,161	69,747
Total rental income	1,194,060	803,455	523,339
Resident fees and services	1,229,479	868,095	446,301
Medical office building and other services revenue	20,741	36,471	14,098
Income from loans and investments	39,913	34,415	16,412
Interest and other income	1,106	1,217	484
Total revenues	2,485,299	1,743,653	1,000,634
Expenses:
Interest	293,401	229,346	172,474
Depreciation and amortization	725,981	447,664	200,682
Property-level operating expenses:
Senior living	843,190	590,151	291,831
Medical office buildings	126,152	57,042	24,122
Total property-level operating expenses	969,342	647,193	315,953
Medical office building services costs	9,883	27,082	9,518
General, administrative and professional fees	98,801	74,537	49,830
Loss on extinguishment of debt, net	37,640	27,604	9,791
Litigation proceeds, net	0	(202,259)	0
Merger-related expenses and deal costs	63,183	153,923	19,243
Other	6,956	7,270	272
Total expenses	2,205,187	1,412,360	777,763
Income before income (loss) from unconsolidated entities, income taxes, discontinued operations and noncontrolling interest	280,112	331,293	222,871
Income (loss) from unconsolidated entities	18,154	(52)	(664)
Income tax benefit (expense)	6,282	30,660	(5,201)
Income from continuing operations	304,548	361,901	217,006
Discontinued operations	57,227	1,360	32,723
Net income	361,775	363,261	249,729
Net (loss) income attributable to noncontrolling interest (net of tax of $0, $0, and $2,271 for the years ended December 31, 2012, 2011 and 2010, respectively)	(1,025)	(1,232)	3,562
Net income attributable to common stockholders	$ 362,800	$ 364,493	$ 246,167
Basic:
Income from continuing operations attributable to common stockholders (in dollars per share)	$ 1.04	$ 1.59	$ 1.36
Discontinued operations (in dollars per share)	$ 0.20	$ 0.01	$ 0.21
Net income attributable to common stockholders (in dollars per share)	$ 1.24	$ 1.60	$ 1.57
Diluted:
Income from continuing operations attributable to common stockholders (in dollars per share)	$ 1.04	$ 1.57	$ 1.35
Discontinued operations (in dollars per share)	$ 0.19	$ 0.01	$ 0.21
Net income attributable to common stockholders (in dollars per share)	$ 1.23	$ 1.58	$ 1.56
Weighted average shares used in computing earnings per common share:
Basic (in shares)	292,064,000	228,453,000	156,608,000
Diluted (in shares)	294,488,000	230,790,000	157,657,000