Real Estate Properties (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended			1 Months Ended		1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2013 item	Sep. 30, 2012	Sep. 30, 2013 item	Sep. 30, 2012	Sep. 30, 2013 MOBs item	Aug. 31, 2013 Skilled nursing facility Sale item	Sep. 30, 2013 Rehabilitation hospitals item	Aug. 31, 2013 Rehabilitation hospitals Purchase Agreement item	Sep. 30, 2013 Discontinued operations, properties sold or held for sale MOBs item	Sep. 30, 2012 Discontinued operations, properties sold or held for sale MOBs	Sep. 30, 2013 Discontinued operations, properties sold or held for sale MOBs item	Sep. 30, 2012 Discontinued operations, properties sold or held for sale MOBs
Real estate properties
Rental income	$ 112,319	$ 113,756	$ 336,468	$ 329,191					$ 2,189	$ 2,525	$ 7,284	$ 7,581
Property operating expenses	(74,729)	(46,805)	(222,893)	(125,109)					(958)	(1,002)	(2,723)	(2,766)
Depreciation and amortization	(38,473)	(35,276)	(114,472)	(102,673)						(604)	(799)	(1,814)
Income from discontinued operations	1,231	919	3,762	3,001					1,231	919	3,762	3,001
Number of properties that met the criteria for discontinued operations	19		19		7		2		7		7
Number of units/beds						112	364
Sale price of property sold and agreed to be sold						2,550		90,000
Gain on the sale of property	$ 1,141	$ (101)	$ 1,141	$ (101)		$ 1,141
Number of properties to be sold								2
Number of properties covered under the agreement								2