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Business and Property Management Agreements with RMR LLC (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 USD ($) employee management_agreement | Mar. 31, 2019 USD ($) | Dec. 31, 2020
Related person transactions |  |  |
Number of employees | employee | 0 |  |
Property management and construction supervision fees | $ 3,192,000 | $ 3,064,000 |
Property management and construction supervision fees paid | 3,443,000 | 3,374,000 |
RMR LLC |  |  |
Related person transactions |  |  |
Business management fees incurred | 5,769,000 | 7,719,000 |
Related party transaction business management fees related to subsidiary level management | 725,000 |  |
Related party transaction business management agreement, annual incentive fee estimate included in management fees | $ 0 | $ 0 |
Senior Living Communities | RMR Inc |  |  |
Related person transactions |  |  |
Number of management agreements | management_agreement | 2 |  |
Subsequent Event | Scenario, Forecast | RMR LLC |  |  |
Related person transactions |  |  |
Period of actual amount of incentive fees |  |  | 3 years

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- Details
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