Real Estate Property Investments (Details)	3 Months Ended			1 Months Ended		3 Months Ended							0 Months Ended	3 Months Ended			1 Months Ended
	Mar. 31, 2015 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2014 USD ($)	Apr. 30, 2015 Subsequent event USD ($)	Apr. 30, 2015 Subsequent event HC-One Facility GBP (£) property	Mar. 31, 2015 Senior housing USD ($)	Mar. 31, 2014 Senior housing USD ($)	Mar. 31, 2015 Life science USD ($)	Mar. 31, 2014 Life science USD ($) property	Mar. 31, 2015 Medical office USD ($)	Mar. 31, 2014 Medical office USD ($)	Mar. 31, 2015 Hospital USD ($)	Mar. 29, 2015 Post-acute/skilled property	Mar. 31, 2015 Post-acute/skilled USD ($)	Mar. 31, 2014 Post-acute/skilled USD ($)	Dec. 31, 2014 Senior housing, life science and medical office USD ($)	Mar. 31, 2015 Chartwell Retirement and Residences [Member] Brookdale Senior Living Subsequent event USD ($) item property	Mar. 31, 2015 Chartwell Retirement and Residences [Member] Senior housing Brookdale Senior Living Subsequent event property	Apr. 30, 2015 Germantown TN Facility [Member] Subsequent event USD ($)	Apr. 30, 2015 Germantown TN Facility [Member] Brookdale Senior Living Subsequent event
Acquisition
Number of facilities acquired																		35
Acquisition of facility																			$ 72,000,000
Other real estate acquisitions
Consideration, Cash Paid	34,248,000					34,068,000	5,473,000			180,000
Loans and Leases Receivable, Gross																			41,000,000
Liabilities assumed	626,000					626,000	1,000
Consideration, Noncontrolling Interest	1,306,000					1,306,000	1,152,000
Assets Acquired, Real Estate	34,530,000					34,350,000	6,626,000			180,000
Assets Acquired, Net Intangibles	1,650,000					1,650,000
Amount of facility converted into sale/leaseback					174,000,000
Number of Facilities					36								9
Deposit related to acquisition	37,000,000
Payments to acquire productive assets	64,793,000	49,068,000		161,000,000		16,172,000	6,950,000	27,391,000	26,762,000	19,233,000	12,975,000	37,000		1,960,000	2,381,000
Number of Facilities Placed into Service									2
Number of Leases																	2
Number of Beds Acquired																	5,025
Amount agreed to be paid																	849,000,000
Noncontrolling interest (as a percent)																	10.00%			10.00%
Management Agreement Term																	7 years
Investment Building and Building Improvements	$ 10,980,848,000		$ 10,972,973,000													$ 25,000,000