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Related Person Transactions (Details) $ in Thousands | Mar. 31, 2019 USD ($) agreement shares | Dec. 31, 2018 USD ($)
--- | --- | ---
RMR Inc | Class A common shares |  |
Related person transactions |  |
Equity securities investment (in shares) | 2,637,408 |
Number of management agreements | agreement | 2 |
Five Star |  |
Related person transactions |  |
Equity securities investment (in shares) | 4,235,000 |
Investment owned, percentage of total shares outstanding | 8.30% |
AIC |  |
Related person transactions |  |
Equity method investments | $ | $ 9,102 | $ 8,632
RMR LLC | Five Star |  |
Related person transactions |  |
Investment owned, percentage of total shares outstanding | 35.40% |

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