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Business and Property Management Agreements with RMR LLC (Details) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 USD ($) employee agreement lease_agreement | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Jan. 31, 2019 USD ($) | Jan. 31, 2018 USD ($)
Related Party Transaction |  |  |  |  |
Number of employees | employee | 0 |  |  |  |
Professional fees | $ 13,805,000 | $ 13,373,000 | $ 11,891,000 |  |
RMR LLC |  |  |  |  |
Related Party Transaction |  |  |  |  |
Management agreement incentive fee payable |  |  |  | $ 40,642,000 | $ 55,740,000
Business management fees incurred | 20,629,000 | 27,399,000 | 35,874,000 |  |
Recognized amortization of the liability | $ 2,974,000 | 2,974,000 | 2,974,000 |  |
Percentage of property management fees payable | 3.00% |  |  |  |
Construction supervision fees payable under property management agreement as a percentage of construction costs | 5.00% |  |  |  |
Property management and construction supervision fees | $ 13,802,000 | 13,141,000 | 12,214,000 |  |
Party transaction property management and construction supervision fees capitalized | 3,718,000 | 2,436,000 | 1,382,000 |  |
Amortization of liability related to property management and construction supervision fees | $ 797,000 | 797,000 | 797,000 |  |
Period over which transition services will be provided by the related party after termination of the agreement | 120 days |  |  |  |
RMR LLC | Operating Expense |  |  |  |  |
Related Party Transaction |  |  |  |  |
Property management and construction supervision fees | $ 10,084,000 | $ 10,705,000 | $ 10,832,000 |  |
Senior Living Communities | Five Star |  |  |  |  |
Related Party Transaction |  |  |  |  |
Number of consecutive renewal terms of agreement | agreement | 2 |  |  |  |
Amended Agreement |  |  |  |  |
Related Party Transaction |  |  |  |  |
Base management fee payable as a percentage of aggregate book value of real estate assets or transferred assets | 0.50% |  |  |  |
Amended Agreement | RMR LLC |  |  |  |  |
Related Party Transaction |  |  |  |  |
Base management fee payable as a percentage of average historical cost of real estate investments, excluding transferred assets for investments exceeding specified amount | 0.50% |  |  |  |
Base management fee payable as a percentage of average historical cost of real estate investments, excluding transferred assets for investments up to specified amount | 0.70% |  |  |  |
Threshold amount of other real estate investments for payment of base management fee | $ 250,000,000 |  |  |  |
Base management fee payable as a percentage of average market capitalization exceeding specified amount | 0.50% |  |  |  |
Threshold amount of average market capitalization for payment of base management fee | $ 250,000,000 |  |  |  |
Base management fee payable as a percentage of average closing price per share of common shares on NYSE | 0.70% |  |  |  |
Incentive management fee payable (as a percent) | 12.00% |  |  |  |
Period of measurement | 3 years |  |  |  |
Top consecutive trading days | 10 days |  |  |  |
Consecutive trading days | 30 days |  |  |  |
Management agreement incentive fee payable | $ 0 |  |  |  |
Incentive management fee cap on common shares | 1.50% |  |  |  |
Amended Agreement | RMR LLC | Up C Transaction |  |  |  |  |
Related Party Transaction |  |  |  |  |
Number of business days notice for termination of property management agreement for convenience by the related party | 60 days |  |  |  |
Window for providing notice of termination of property management agreement for performance by the related party | 60 days |  |  |  |
Window for providing notice of termination of property management agreement for change of control by the related party | 12 months |  |  |  |
Number of terminated management agreements for convenience before termination fee is incurred | lease_agreement | 1 |  |  |  |
Number of RMR LLC terminated management agreements for good cause before termination fee is incurred | lease_agreement | 1 |  |  |  |
Number of terminated management agreements for a performance reason before termination fee is incurred | lease_agreement | 1 |  |  |  |
Termination fee remaining term assumption | 10 years |  |  |  |
Maximum | RMR LLC |  |  |  |  |
Related Party Transaction |  |  |  |  |
Threshold amount of real estate investments for payment of base management fee | $ 250,000,000 |  |  |  |
Base management fee payable, average market capitalization | $ 250,000,000 |  |  |  |
Maximum | Amended Agreement | RMR LLC | Up C Transaction |  |  |  |  |
Related Party Transaction |  |  |  |  |
Termination fee term | 20 years |  |  |  |
Minimum | Amended Agreement | RMR LLC | Up C Transaction |  |  |  |  |
Related Party Transaction |  |  |  |  |
Termination fee term | 19 years |  |  |  |
SNL US REIT Healthcare Index | Maximum | Amended Agreement | RMR LLC |  |  |  |  |
Related Party Transaction |  |  |  |  |
Incentive management fee reduction, basis spread | 5.00% |  |  |  |
SNL US REIT Healthcare Index | Minimum | Amended Agreement | RMR LLC |  |  |  |  |
Related Party Transaction |  |  |  |  |
Incentive management fee reduction, basis spread | 2.00% |  |  |  |

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- Definition Represents the number of management agreements RMR LLC would need to terminate for good cause before a termination fee is incurred. + References No definition available. + Details
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- Definition Represents the number of management agreements the company would need to terminate for a performance reason before a termination fee is incurred. + References No definition available. + Details
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- Definition Represents the base management fees payable as a percentage of average historical cost of real estate investments, excluding transferred assets for investments exceeding specified amount. + References No definition available. + Details
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- Definition Represents the base management fees payable as a percentage of average historical cost of real estate investments, excluding transferred assets for investments up to specified amount. + References No definition available. + Details
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- Definition Represents the threshold amount of other real estate investments for payment of base management fee. + References No definition available. + Details
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- Definition Related Party Transaction, Incentive Management Fee, Top Consecutive Trading Days + References No definition available. + Details
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- Definition Represents the window or numbers of business days after any calendar year to provide notice for termination of property management agreement by the related party for performance reasons. + References No definition available. + Details
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- Definition Represents the number of business days notice for termination of property management agreement by the related party for convenience. + References No definition available. + Details
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- Definition Represents the incentive management fee payable as a percentage of the product of the entity's equity market capitalization and its share price appreciation plus dividends. + References No definition available. + Details
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- Definition Represents the period over which the related party agrees to provide certain transition services following an applicable termination of the agreement. + References No definition available. + Details
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- Definition Represents the window after a change in control to provide notice for termination of property management agreement by the related party. + References No definition available. + Details
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- Definition Represents the remaining term assumption in years used to calculate the fee for termination of one or both of the company's amended management agreements for a performance reason. + References No definition available. + Details
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