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Shareholders' Equity - Narrative (Details) $ / shares in Units, $ in Thousands		1 Months Ended		12 Months Ended
	Jan. 15, 2026 USD ($) $ / shares	Mar. 31, 2025 USD ($) trustee shares	Sep. 30, 2023 USD ($) trustee shares	Dec. 31, 2025 USD ($) shares	Dec. 31, 2024 USD ($) shares	Dec. 31, 2023 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense				$ 3,411	$ 2,747	$ 1,840
Distributions				$ 9,661	$ 9,627	$ 9,595
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award
Common distributions declared (in dollars per share) \| $ / shares	$ 0.01
Distributions	$ 2,421
RMR LLC
Share-based Compensation Arrangement by Share-based Payment Award
Shares purchased from certain of our officers and other employees of RMR LLC (in shares) \| shares				276,078	268,221	184,344
Share Award Plans
Share-based Compensation Arrangement by Share-based Payment Award
Remaining common shares available for issuance (in shares) \| shares				3,493,033
Estimated future compensation for the unvested shares				$ 4,670
Weighted average period over which the compensation expense will be recorded				1 year 10 months 24 days
Share Award Plans \| RMR LLC
Share-based Compensation Arrangement by Share-based Payment Award
Number of trustees elected \| trustee		1	1
Officers and Other Employees \| Share Award Plans \| RMR LLC
Share-based Compensation Arrangement by Share-based Payment Award
Common shares awarded (in shares) \| shares				950,895	881,767	800,000
Aggregate market value of shares awarded				$ 4,070	$ 2,954	$ 1,864
Award vesting period				5 years
Trustees \| Share Award Plans \| RMR LLC
Share-based Compensation Arrangement by Share-based Payment Award
Common shares awarded (in shares) \| shares		33,582	20,000	29,141	37,037,000	20,000
Aggregate market value of shares awarded		$ 90	$ 45	$ 665	$ 630	$ 244
Market value of shares awarded to each Trustee				$ 95	$ 90	$ 35