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Related Person Transactions (Details) $ in Thousands |  |  | 1 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | ---
Sep. 24, 2018 shares | Sep. 13, 2018 shares | Sep. 30, 2018 USD ($) agreement shares | Sep. 30, 2017 shares | Mar. 31, 2017 building | Sep. 30, 2018 USD ($) building agreement shares | Dec. 31, 2017 USD ($)
Related person transactions |  |  |  |  |  |  |
Number of buildings included in joint venture agreement | building |  |  |  |  | 2 |  |
RMR Inc | Class A common shares |  |  |  |  |  |  |
Related person transactions |  |  |  |  |  |  |
Equity securities investment (in shares) |  |  | 2,637,408 |  |  | 2,637,408 |
Number of management agreements | agreement |  |  | 2 |  |  | 2 |
Five Star |  |  |  |  |  |  |
Related person transactions |  |  |  |  |  |  |
Equity securities investment (in shares) |  |  | 4,235,000 |  |  | 4,235,000 |
Investment owned, percentage of total shares outstanding |  |  | 8.40% |  |  | 8.40% |
Employees Of RMR LLC |  |  |  |  |  |  |
Related person transactions |  |  |  |  |  |  |
Shares issued in period (in shares) |  | 105,800 | 105,800 | 88,100 |  |  |
Shares purchased to satisfy tax withholding and payment obligations (in shares) | 18,121 |  | 18,121 | 16,654 |  |  |
AIC |  |  |  |  |  |  |
Related person transactions |  |  |  |  |  |  |
Property insurance annual premium | $ |  |  |  |  |  | $ 4,413 |
Equity method investments | $ |  |  | $ 9,157 |  |  | $ 9,157 | $ 8,185
RMR LLC | Five Star |  |  |  |  |  |  |
Related person transactions |  |  |  |  |  |  |
Investment owned, percentage of total shares outstanding |  |  | 35.60% |  |  | 35.60% |
MOBs |  |  |  |  |  |  |
Related person transactions |  |  |  |  |  |  |
Standalone insurance policy coverage period |  |  |  |  |  | 1 year |
Number of buildings included in joint venture agreement | building |  |  |  |  |  | 2 |

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