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Related Person Transactions (Details) $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2020 USD ($) | Sep. 30, 2020 USD ($) agreement shares | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) agreement shares | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($)
Related person transactions |  |  |  |  |  |
Proceeds from sale of equity method investments |  |  |  | $ 287 | $ 0 |
Equity in earnings of an investee |  | $ 0 | $ 83 | $ 0 | $ 617 |
Five Star |  |  |  |  |  |
Related person transactions |  |  |  |  |  |
Equity securities investment (in shares) | shares |  | 10,691,658 |  | 10,691,658 |  |
Investment owned, percentage of total shares outstanding |  | 33.90% |  | 33.90% |  |
RMR LLC |  |  |  |  |  |
Related person transactions |  |  |  |  |  |
Number of management agreements | agreement |  | 2 |  | 2 |  |
AIC |  |  |  |  |  |
Related person transactions |  |  |  |  |  |
Equity method investments |  | $ 11 |  | $ 11 |  | $ 298
Proceeds from sale of equity method investments | $ 287 |  |  |  |  |
Equity in earnings of an investee |  | $ 83 |  | 617 |  |
Five Star |  |  |  |  |  |
Related person transactions |  |  |  |  |  |
Property insurance program costs |  |  |  | $ 500 |  |
RMR LLC | Five Star |  |  |  |  |  |
Related person transactions |  |  |  |  |  |
Investment owned, percentage of total shares outstanding |  | 6.40% |  | 6.40% |  |

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