Supplemental Disclosure of Cash Flow Information - Narrative (Details) $ in Thousands		1 Months Ended	3 Months Ended		9 Months Ended		21 Months Ended
	Jul. 01, 2021 USD ($)	Oct. 31, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) community	Sep. 30, 2021 USD ($) community	Sep. 30, 2022 USD ($) community	Dec. 31, 2021 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of communities acquired | community							1
Gain (loss) on sale of assets, net			$ (56)	$ 288,375	$ 611	$ 289,408
Investment in unconsolidated ventures			$ 57,701		$ 57,701		$ 57,701	$ 67,424
Securities Purchase Agreement | HCA Healthcare, Inc. | Health Care Services
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net cash proceeds	$ 305,800
Sale of stock, percentage of ownership sold in transaction (as a percent)	80.00%
Purchase price	$ 400,000
Net cash proceeds	312,600
Proceeds from post closing working capital adjustment		$ 6,800
Investment in unconsolidated ventures	$ 100,000
Sale of stock, percentage of ownership after transaction (as a percent)	20.00%
Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of communities disposed of | community					2	2	5
Net cash proceeds					$ 4,400	$ 8,500
Gain (loss) on sale of assets, net					$ 700	$ 500
Communities Disposed of Through Lease Terminations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of communities disposed of | community							6