Real Property Acquisitions and Development (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Senior housing - triple net [Member]
Estimated Fair Value of Allocated Purchase Price of Asset and Liabilities
Land and land improvements	$ 8,533	[1]	$ 5,950
Buildings and improvements	47,993	[1]	89,333
Total assets acquired	56,526	[1]	95,283
Assumed debt	0	[1]	0
Accrued expenses and other liabilities	0	[1]	(232)
Capital in excess of par	0	[1]	0
Noncontrolling interests	0	[1]	0
Non-cash acquisition related activity	0	[1]	0
Cash disbursed for acquisitions	56,526	[1]	95,051
Construction in progress additions	23,946	[1]	38,467
Less: Capitalized Interest	(1,227)	[1]	(1,242)
Cash disbursed for construction in progress	22,719	[1]	37,225
Capital improvements to existing properties	8,336	[1]	9,948
Total cash invested in real property	87,581	[1]	142,224
Total purchase price	56,526
Senior housing - operating [Member]
Estimated Fair Value of Allocated Purchase Price of Asset and Liabilities
Land and land improvements	216,949	[2]	18,980
Buildings and improvements	2,074,770	[2]	174,467
Acquired lease intangibles	142,054	[2]	16,656
Restricted cash	22,863	[2]	0
Investment in unconsolidated entities	0	[2]	0
Receivables and other assets	3,225	[2]	1,182
Total assets acquired	2,459,861	[2],[3]	211,285	[3]
Assumed debt	(138,259)	[2]	0
Accrued expenses and other liabilities	(31,302)	[2]	(1,649)
Total liabilities assumed	(169,561)	[2]	(1,649)
Capital in excess of par	0	[2]	0
Noncontrolling interests	(4,868)	[2]	(2,054)
Non-cash acquisition related activity	(555,562)	[2],[4]	0	[4]
Cash disbursed for acquisitions	1,729,870	[2]	207,582
Construction in progress additions	235	[2]	0
Less: Capitalized Interest	(2)	[2]	0
Cash disbursed for construction in progress	233	[2]	0
Capital improvements to existing properties	10,604	[2]	3,040
Total cash invested in real property	1,740,707	[2]	210,622
Cash Acquired from Acquisition	51,803		1,619
Total purchase price	2,819,436
Medical facilities [Member]
Estimated Fair Value of Allocated Purchase Price of Asset and Liabilities
Land and land improvements	0		9,509
Buildings and improvements	0		320,481
Acquired lease intangibles	0		39,619
Restricted cash	0		0
Receivables and other assets	0		4,158
Total assets acquired	0		373,767
Assumed debt	0		(172,856)
Accrued expenses and other liabilities	0		(9,255)
Total liabilities assumed	0		(182,111)
Cash disbursed for acquisitions	0		191,656
Construction in progress additions	35,139		40,557
Less: Capitalized Interest	(377)		(1,178)
Less: Accruals	(17,661)	[5]	(20,752)	[5]
Cash disbursed for construction in progress	17,101		18,627
Capital improvements to existing properties	5,189		7,071
Total cash invested in real property	$ 22,290		$ 217,354

[1] (1) Includes acquisitions with an aggregate purchase price of $56,526,000 for which the allocation of the purchase price consideration is preliminary and subject to change.

[2] (2) Includes acquisitions with an aggregate purchase price of $2,819,436,000 for which the allocation of the purchase price consideration is preliminary and subject to change.

[3] (1) Excludes $51,803,000 and $1,619,000 of cash acquired during the three months ended March 31, 2013 and 2012, respectively.

[4] (3) Represents Sunrise loan and noncontrolling interests acquisitions.

[5] (1) Represents non-cash accruals for amounts to be paid in future periods relating to properties that converted in the periods noted above.