Dispositions of Real Estate and Discontinued Operations (Details) (USD $)	12 Months Ended					1 Months Ended	12 Months Ended
	Dec. 31, 2013 item	Dec. 31, 2012 item	Dec. 31, 2011 item	Dec. 31, 2013 Medical office item	Dec. 31, 2012 Medical office item	Sep. 30, 2013 Hospital item	Dec. 31, 2013 Hospital item	Dec. 31, 2012 Hospital item	Dec. 31, 2013 Senior housing item	Dec. 31, 2012 Senior housing item	Dec. 31, 2013 Post-acute/skilled nursing item	Dec. 31, 2012 Post-acute/skilled nursing	Dec. 31, 2012 Parcel of land in the life science segment	Dec. 31, 2013 Post-acute/skilled nursing and senior housing	Dec. 31, 2012 Senior housing and hospital and medical office
Dispositions of Real Estate and Land
Number of properties disposed				2					2	2	8
Total consideration for disposition of real estate				$ 6,000,000	$ 7,000,000				$ 22,000,000	$ 111,000,000	$ 68,000,000	$ 15,000,000	$ 18,000,000
Number of beds sold						62
Number of beds acquired						60
Number of properties held for sale					2		1	2		12	2
Carrying value of properties classified as held for sale	9,819,000	56,659,000												10,000,000	56,000,000
Gain on sales of real estate, net of income taxes	69,866,000	31,454,000	3,107,000			8,000,000
Operating income from discontinued operations
Rental and related revenues	16,649,000	33,777,000	32,555,000
Depreciation and amortization expenses	5,862,000	12,808,000	11,340,000
Operating expenses	3,929,000	3,304,000	1,472,000
Other expense, net	979,000	3,467,000	4,486,000
Income before impairments and gain on sales of real estate, net of income taxes	5,879,000	14,198,000	15,257,000
Impairments	$ 1,372,000
Number of properties included in discontinued operations	16	20	23