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Shareholders' Equity - Narrative (Details) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Jan. 16, 2025 USD ($) $ / shares	Sep. 30, 2023 USD ($) trustee shares	Dec. 31, 2024 USD ($) shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense			$ 2,747	$ 1,840	$ 1,733
Distributions			$ 9,627	$ 9,595	$ 9,568
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award
Common distributions declared (in dollars per share) \| $ / shares	$ 0.01
Distributions	$ 2,413
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			268,221	184,344	133,752
Share Award Plans
Share-based Compensation Arrangement by Share-based Payment Award
Remaining common shares available for issuance (in shares) \| shares			1,090,392
Estimated future compensation for the unvested shares			$ 3,323
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
Officers and Other Employees \| Share Award Plans \| RMR LLC
Share-based Compensation Arrangement by Share-based Payment Award
Common shares awarded (in shares) \| shares			881,767	800,000	707,000
Aggregate market value of shares awarded			$ 2,954	$ 1,864	$ 919
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		20,000	37,037	20,000	20,000
Aggregate market value of shares awarded		$ 45	$ 630	$ 244	$ 300
Market value of shares awarded to each Trustee			$ 90	$ 35	$ 43