Variable Interest Entities - Schedule of Variable Interest Entities (Details) $ in Thousands	Sep. 30, 2019 USD ($)
VIE tenants-operating leases
Variable Interest Entity [Line Items]
Maximum Loss Exposure and Carrying Amount	$ 7,984
CCRC OpCo
Variable Interest Entity [Line Items]
Maximum Loss Exposure and Carrying Amount	167,612
Unconsolidated Development JVs
Variable Interest Entity [Line Items]
Maximum Loss Exposure and Carrying Amount	24,015
Loan - seller financing
Variable Interest Entity [Line Items]
Maximum Loss Exposure and Carrying Amount	10,000
CMBS and LLC investment
Variable Interest Entity [Line Items]
Maximum Loss Exposure and Carrying Amount	$ 34,677