Accounting policies.

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Concentration of credit risk, resident receivables period.

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Number Of Communities

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Other Income, Grants

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Percentage Of Voting Rights

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Residency Agreements, Termination Notice Period

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Amount of allowance for credit loss on accounts receivable.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Summary of Significant Accounting Policies - Narrative (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2024 USD ($) property seniorHousingCommunity	Jun. 30, 2023 USD ($) property seniorHousingCommunity	Jun. 30, 2024 USD ($) segment property seniorHousingCommunity	Jun. 30, 2023 USD ($) property seniorHousingCommunity	Dec. 31, 2023 USD ($)
Accounting Policies [Line Items]
Non-cash impairment charge on property and equipment \| $	$ 0	$ 0	$ 0	$ 0
Termination notice period			30 days
Number of communities \| seniorHousingCommunity	22	23	22	24
Grants receivables \| $		$ 400,000	$ 0	$ 2,400,000
Resident receivables due period			30 days
Allowance for doubtful accounts \| $	$ 6,100,000		$ 6,100,000		$ 5,300,000
Number of senior housing communities \| seniorHousingCommunity	78		78
Percentage of voting rights	0.50		0.50		0.50
Number of reportable segments \| segment			1
Number of operating segments \| segment			1
Properties \| Geographic Concentration Risk \| Texas
Accounting Policies [Line Items]
Concentration risk percentage	23.00%	23.00%	23.00%	24.00%
Number of senior housing communities \| property	16	16	16	16
Properties \| Geographic Concentration Risk \| Indiana
Accounting Policies [Line Items]
Concentration risk percentage	18.00%	18.00%	18.00%	18.00%
Number of senior housing communities \| property	12	12	12	12
Properties \| Geographic Concentration Risk \| Ohio
Accounting Policies [Line Items]
Concentration risk percentage	21.00%	20.00%	20.00%	20.00%
Number of senior housing communities \| property	11	11	11	11
Properties \| Geographic Concentration Risk \| Wisconsin
Accounting Policies [Line Items]
Concentration risk percentage	10.00%	11.00%	10.00%	10.00%
Number of senior housing communities \| property	8	8	8	8
Housing And Support Services
Accounting Policies [Line Items]
Contract liabilities for deferred fees paid \| $	$ 4,400,000		$ 4,400,000		$ 4,000,000.0
Medicaid Program Revenue \| Revenue Benchmark \| Customer Concentration Risk
Accounting Policies [Line Items]
Concentration risk percentage	11.10%	9.40%	11.30%	9.40%