Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 1,042,044	$ 1,187,234
Private pay
Disaggregation of Revenue [Line Items]
Revenue	648,679	742,761
Government reimbursement
Disaggregation of Revenue [Line Items]
Revenue	127,408	135,239
Other third-party payor programs
Disaggregation of Revenue [Line Items]
Revenue	33,392	28,266
Resident fees
Disaggregation of Revenue [Line Items]
Revenue	809,479	906,266
Independent Living | Private pay
Disaggregation of Revenue [Line Items]
Revenue	135,045	157,507
Independent Living | Government reimbursement
Disaggregation of Revenue [Line Items]
Revenue	649	890
Independent Living | Other third-party payor programs
Disaggregation of Revenue [Line Items]
Revenue	0	0
Independent Living | Resident fees
Disaggregation of Revenue [Line Items]
Revenue	135,694	158,397
Assisted Living and Memory Care | Private pay
Disaggregation of Revenue [Line Items]
Revenue	441,911	514,264
Assisted Living and Memory Care | Government reimbursement
Disaggregation of Revenue [Line Items]
Revenue	16,615	18,016
Assisted Living and Memory Care | Other third-party payor programs
Disaggregation of Revenue [Line Items]
Revenue	0	0
Assisted Living and Memory Care | Resident fees
Disaggregation of Revenue [Line Items]
Revenue	458,526	532,280
CCRCs | Private pay
Disaggregation of Revenue [Line Items]
Revenue	71,533	70,721
CCRCs | Government reimbursement
Disaggregation of Revenue [Line Items]
Revenue	21,487	23,706
CCRCs | Other third-party payor programs
Disaggregation of Revenue [Line Items]
Revenue	10,707	10,642
CCRCs | Resident fees
Disaggregation of Revenue [Line Items]
Revenue	103,727	105,069
Health Care Services | Private pay
Disaggregation of Revenue [Line Items]
Revenue	190	269
Health Care Services | Government reimbursement
Disaggregation of Revenue [Line Items]
Revenue	88,657	92,627
Health Care Services | Other third-party payor programs
Disaggregation of Revenue [Line Items]
Revenue	22,685	17,624
Health Care Services | Resident fees
Disaggregation of Revenue [Line Items]
Revenue	$ 111,532	$ 110,520