Concentration of Credit Risk - Senior Living Operations (Details)	Dec. 31, 2019 property
Concentration Risk [Line Items]
Number of real estate properties	1,200
Consolidated Seniors Housing Communities
Concentration Risk [Line Items]
Number of real estate properties	401
Atria and Sunrise \| Consolidated Seniors Housing Communities
Concentration Risk [Line Items]
Number of real estate properties	260

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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