Disaggregation of Revenue - Disaggregation of Revenue (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)
Disaggregation of Revenue [Line Items]
Revenue	$ 3,449,211
Private pay
Disaggregation of Revenue [Line Items]
Revenue	2,809,903
Government reimbursement
Disaggregation of Revenue [Line Items]
Revenue	522,209
Other third-party payor programs
Disaggregation of Revenue [Line Items]
Revenue	117,099
Independent Living
Disaggregation of Revenue [Line Items]
Revenue	599,977
Independent Living | Private pay
Disaggregation of Revenue [Line Items]
Revenue	596,852
Independent Living | Government reimbursement
Disaggregation of Revenue [Line Items]
Revenue	3,125
Independent Living | Other third-party payor programs
Disaggregation of Revenue [Line Items]
Revenue	0
Assisted Living and Memory Care
Disaggregation of Revenue [Line Items]
Revenue	1,995,851
Assisted Living and Memory Care | Private pay
Disaggregation of Revenue [Line Items]
Revenue	1,923,676
Assisted Living and Memory Care | Government reimbursement
Disaggregation of Revenue [Line Items]
Revenue	72,175
Assisted Living and Memory Care | Other third-party payor programs
Disaggregation of Revenue [Line Items]
Revenue	0
CCRCs
Disaggregation of Revenue [Line Items]
Revenue	416,408
CCRCs | Private pay
Disaggregation of Revenue [Line Items]
Revenue	288,682
CCRCs | Government reimbursement
Disaggregation of Revenue [Line Items]
Revenue	87,028
CCRCs | Other third-party payor programs
Disaggregation of Revenue [Line Items]
Revenue	40,698
Health Care Services
Disaggregation of Revenue [Line Items]
Revenue	436,975
Health Care Services | Private pay
Disaggregation of Revenue [Line Items]
Revenue	693
Health Care Services | Government reimbursement
Disaggregation of Revenue [Line Items]
Revenue	359,881
Health Care Services | Other third-party payor programs
Disaggregation of Revenue [Line Items]
Revenue	$ 76,401