Related Person Transactions (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			0 Months Ended									12 Months Ended							12 Months Ended					1 Months Ended			12 Months Ended					1 Months Ended		1 Months Ended			1 Months Ended							12 Months Ended	1 Months Ended	12 Months Ended		1 Months Ended				1 Months Ended
	Dec. 31, 2013 property	Dec. 31, 2012	Dec. 31, 2011	Apr. 30, 2013 SNF	Dec. 31, 2013 SNF unit	Oct. 31, 2012 SNF property	Sep. 30, 2012 SNF property	Sep. 30, 2011 SNF property	Dec. 31, 2013 Assisted living communities property unit	Jun. 30, 2013 Assisted living communities property	Dec. 31, 2013 First AL Pooling Agreements property	Dec. 31, 2013 Second AL Pooling Agreements property	Dec. 31, 2013 IL Pooling Agreement item	Dec. 31, 2012 Bridge Loan	Dec. 31, 2011 Bridge Loan	Dec. 31, 2013 Senior Living Communities unit property	Aug. 31, 2013 Rehabilitation hospitals property	Dec. 31, 2013 Assisted living communities unit	Dec. 31, 2013 Assisted living communities property	Dec. 31, 2013 SNH item property	Dec. 31, 2012 SNH	Dec. 31, 2011 SNH	Aug. 31, 2012 SNH property	Jun. 30, 2013 SNH Senior Living Communities property	Aug. 31, 2013 SNH SNF unit property	Jun. 30, 2013 SNH SNF property	Jun. 30, 2013 SNH Assisted living communities property	Dec. 31, 2013 SNH AL Pooling Agreements	Dec. 31, 2013 SNH Bridge Loan	Dec. 31, 2012 SNH Bridge Loan	Dec. 31, 2011 SNH Bridge Loan	May 31, 2011 SNH Bridge Loan	Apr. 30, 2012 SNH Bridge Loan Annual rates of interest applicable to borrowings under revolving credit facility	Jul. 10, 2014 SNH Subsequent event item	Jun. 30, 2014 SNH Subsequent event SNF property unit	Jan. 31, 2014 SNH Subsequent event Assisted living communities property unit	Jul. 31, 2014 SNH Subsequent event SNF and assisted living communities property	Aug. 31, 2013 SNH Senior Living Communities property	Dec. 31, 2013 SNH Senior Living Communities property	Oct. 31, 2013 SNH Senior Living Communities property unit	Oct. 31, 2013 SNH Senior Living Communities Georgia property	Aug. 31, 2013 SNH Senior Living Communities Georgia property	Oct. 31, 2013 SNH Senior Living Communities Tennessee property	Nov. 30, 2013 SNH Senior Living Communities Wisconsin property	Dec. 31, 2013 SNH Senior Living Communities New York property	Jan. 31, 2014 SNH Senior Living Communities Subsequent event property	Dec. 31, 2013 SNH Senior Living Communities D&R Yonkers LLC item	Dec. 31, 2013 SNH Senior Living Communities D&R Yonkers LLC New York property	Dec. 31, 2013 SNH Rehabilitation hospitals property	Sep. 30, 2013 SNH Rehabilitation hospitals Lease No. 2	Dec. 31, 2013 SNH Outpatient clinics property	Dec. 31, 2013 SNH Assisted living communities property unit	Jan. 31, 2014 SNH Assisted living communities Subsequent event unit
Related person transactions
Ownership percentage by former parent																				100.00%
Number of shares owned																				4,235
Percentage of outstanding common shares owned																				8.70%
Minimum percentage of ownership interest beyond which consent of related party required																				9.80%
Minimum percentage of ownership interest of voting stock above which the option to cancel all the lease rights exist																				9.80%
Number of real estate properties leased	191															181	2																						187
Number of real estate properties classified as discontinued operations						2	2	2	1									32	1	4																	2		10													4
Total minimum annual rent payable	$ 2,097,188																			$ 190,135
Rent expense under leases, net of lease inducement amortization																				202,868	200,036	194,524
Outstanding rent due and payable																				17,960	17,688
Real estate improvements sold																				27,208	30,520	33,269
Increase (decrease) in annual lease rent payable																				2,177	2,456	2,665																												(9,500)
Assets held for sale for increased rent pursuant to the terms of leases with SNH																				9,342	9,625
Number of properties to be sold										1														10	1	7	3
Decrease in annual lease rent payable																									255										450	210																	210
Number of real estate properties offered for sale classified as discontinued operations																																							10
Number of real estate properties sold																																			2	1		1								1			2		13
Proceeds from sale of real estate																																																	90,000
Net assets retained																																																	9,591
Number of remaining real estate properties classified as discontinued operations																																						3
Number of properties managed											20	19				44																							44
Incentive fee as a percentage of the annual net operating income after the entity realizes an annual return equal to 8% of invested capital																				35.00%
Annual return as a percentage of invested surplus specified as a base for determining incentive fee																				8.00%
Number of consecutive renewal terms of agreement																																															9
Renewal term of the property management agreement																																															5 years
Minimum percentage of ownership interest of lessee's voting stock above which the entity has the option to cancel all its rights																				9.80%
Number of combination agreements																				4
Number of pooling agreements for communities that include assisted living units																				3
Number of communities													2
Number of consecutive periods during which the entity must not receive the minimum return for the property management agreement to be subject to the pooling agreement																												3 years
Management fee revenue	9,234	5,817	898																	9,229	5,582	835
Number of additional properties managed																																								3	2		1
Number of units in additional properties managed																																								213
Number of units in properties managed																7,051																										93		68	199			111
Number of independent living communities for which agreement is entered for extension of term																																		2
Management fees receivable under property management agreement as a percentage of gross revenues																				3.00%																									5.00%		3.00%
Incentive fee payable under the management agreement																																													0
Number of units in real estate property offered for sale					271				32																112										155	48																712	48
Sales price				8,000																					2,550										4,500	2,400																	2,400
Decrease in annual lease rent payable as a percentage of net proceeds of sale																									10.00%										10.00%	8.75%																	8.75%
Loan amount																															80,000	80,000
Interest rate margin over base rate																																	1.00%
Interest expense														$ 314	$ 593														$ 0	$ 314	$ 593
Number of properties securing a debt released as a result of repayment of related debt																							11
Number of properties securing a debt																							28