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Represents the number of communities managed by a related party.

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Expenses recognized during the period resulting from property management transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

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Related Party Transaction, Percentage of Annual Incentive Fee

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Represents the management fees payable to related parties under property management agreement expressed as a percentage of gross revenues.

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Related Party Transaction, Property Management Agreement, Management Fees As Percentage Of Gross Revenues Realized At All Communities

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Related Party Transaction, Property Management Agreement, Renewal Term

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Related Party Transactions, Maximum Amount Of Contracts That Can Be Terminated Termination Percentage

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Revenue Reserve, Inadequate Documentation

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Trigger Basis For Capital Investments

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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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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Amount of gain (loss) on termination of lease before expiration of lease term.

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The number of real estate properties owned as of the balance sheet date.

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The number of units in a real estate property owned as of the balance sheet date.

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Amount paid to managing member or general partner for management of the day-to-day business functions of the limited liability company (LLC) or limited partnership (LP).

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Amount of transactions with related party during the financial reporting period.

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Senior Living Community Management Agreements - Narrative (Details) $ in Thousands			1 Months Ended	12 Months Ended
	Nov. 01, 2022 USD ($)	Jun. 09, 2021 USD ($) community unit	Jan. 31, 2021 USD ($)	Dec. 31, 2022 USD ($) property trustee option community unit shares	Dec. 31, 2021 USD ($) community property unit shares	Dec. 31, 2020 USD ($) property community	Jan. 01, 2020 shares
Concentration Risk
Common shares, shares issued (in shares) \| shares				239,694,842	238,994,894
Gain on lease termination				$ 0	$ 0	$ 22,896
Number of properties owned (property) \| property				379
Management agreement, term				5 years
Management agreement, extension term				2 years
Management fees payable to third parties				$ 20,739	$ 6,239
AlerisLife Inc
Concentration Risk
Common shares, shares issued (in shares) \| shares							10,268,158
Aggregate shares issued (shares) \| shares							16,118,849
Senior Living Communities
Concentration Risk
Number of properties owned (property) \| property						28
Number of units in real estate property \| unit				27,408
Number of communities managed \| community				111	107
Senior Living Communities \| Minimum
Concentration Risk
Management fees as a percentage of gross revenues				5.00%
Percentage of annual incentive fee				15.00%
Construction supervision fee				3.00%
Property management agreement, management fees				70.00%
Senior Living Communities \| Maximum
Concentration Risk
Management fees as a percentage of gross revenues				6.00%
Percentage of annual incentive fee				25.00%
Construction supervision fee				5.00%
Property management agreement, management fees				80.00%
Affiliated Entity \| Five Star
Concentration Risk
Amounts of transaction						$ 75,000
Gain on lease termination						22,896
Management fees as a percentage of gross revenues				5.00%
Percentage of annual incentive fee				15.00%
Consumer price index annual estimated increase				2.00%
Trigger basis for capital investment ratio (percent)				6.00%
Business and property management agreement, number of agreements \| option				2
Renewal term (years)				5 years
Expenses from property management agreement transactions with related party				$ 37,037	$ 47,479	62,880
Related party transaction capitalized amount				3,300	3,615	2,467
Payments made in exchange for customary release			$ 5,763
Refunded management fees			$ 115
Affiliated Entity \| Five Star \| Property Operating Expense
Concentration Risk
Expenses from property management agreement transactions with related party				$ 33,737	$ 43,864	$ 60,413
Affiliated Entity \| Five Star \| Senior Living Communities
Concentration Risk
Number of communities managed \| community				119	120	235
Expenses from transactions with related party				$ 6,289	$ 11,233	$ 25,687
Number of real estate properties inadequate documentation \| trustee				1
Five Star \| Senior Living Communities
Concentration Risk
Number of properties owned (property) \| community		120
Number of real estate properties managed \| community		119
Related party transactions, termination percentage		10.00%
Percentage of EBITDA threshold for contract termination		80.00%
Five Star Management
Concentration Risk
Termination fees paid	$ 350
Disposal Group, Held-for-sale, Not Discontinued Operations \| Senior Living Communities
Concentration Risk
Number of properties owned (property) \| property						10
Disposal Group, Held-for-sale, Not Discontinued Operations \| Five Star \| Senior Living Communities
Concentration Risk
Amounts of transaction		$ 682,000
Number of properties owned (property) \| community		108			108
Number of units in real estate property \| unit		1,500
Disposal Group, Disposed of by Means Other than Sale, Not Discontinued Operations \| Five Star \| Senior Living Communities
Concentration Risk
Amounts of transaction				$ 2,096	$ 17,363
Number of units in real estate property \| unit					7,340
Number of properties transitioned \| community					107
Scenario, Adjustment \| Senior Living Communities
Concentration Risk
Number of properties owned (property) \| property					10
Scenario, Adjustment \| Disposal Group, Held-for-sale, Not Discontinued Operations \| Five Star \| Senior Living Communities
Concentration Risk
Number of units in real estate property \| unit		7,500
Residents fees and services \| SHOP \| Affiliated Entity \| Five Star
Concentration Risk
Revenue reserve for inadequate documentation						$ 3,842
Penalties for inadequate documentation						$ 1,921