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Related Person Transactions (Details) $ / shares in Units, $ in Thousands					12 Months Ended
	Jan. 09, 2026 USD ($)	Jul. 15, 2025 USD ($)	Feb. 14, 2025 USD ($)	Feb. 16, 2024 USD ($)	Dec. 31, 2025 USD ($) agreement	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($) $ / shares	Mar. 20, 2023
Related Party Transaction
Equity method investment distributions					$ 48,400	$ 0	$ 0
Revenues					1,537,853	1,495,427	1,410,308
Rental income
Related Party Transaction
Revenues					225,198	251,038	258,400
RMR LLC \| Rental income
Related Party Transaction
Revenues					$ 423	$ 460	$ 196
AlerisLife Inc
Related Party Transaction
Step acquisition, ownership percentage including subsequent acquisition				34.00%
Purchase price				$ 15,459
Related Party \| RMR LLC
Related Party Transaction
Number of management agreements \| agreement					2
Related party transaction, closing cost					$ 3,965
AlerisLife Inc
Related Party Transaction
Investment owned balance per shares (in dollars per share) \| $ / shares							$ 1.31
Equity method investment distributions		$ 3,400	$ 17,000
AlerisLife Inc \| Subsequent Event
Related Party Transaction
Equity method investment distributions	$ 27,200
AlerisLife Inc \| Related Party
Related Party Transaction
Investment owned, percentage of total shares outstanding								31.90%
AlerisLife Inc
Related Party Transaction
Payments of dividend		$ 10,000	$ 50,000
AlerisLife Inc \| Subsequent Event
Related Party Transaction
Payments of dividend	$ 80,000
RMR LLC \| Year one
Related Party Transaction
Award vesting rights, percentage					20.00%
RMR LLC \| Year two
Related Party Transaction
Award vesting rights, percentage					20.00%
RMR LLC \| Year three
Related Party Transaction
Award vesting rights, percentage					20.00%
RMR LLC \| Year four
Related Party Transaction
Award vesting rights, percentage					20.00%
RMR LLC \| Year five
Related Party Transaction
Award vesting rights, percentage					20.00%
Diversified Healthcare Trusts \| ABP Trust and Adam D. Portnoy
Related Party Transaction
Noncontrolling interest, ownership percentage by parent					9.80%
AlerisLife Inc \| ABP Acquisition LLC And ABP Trust
Related Party Transaction
Noncontrolling interest, ownership percentage by parent								6.10%