Business and Property Management Agreements with RMR LLC (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) employee agreement	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) employee agreement	Sep. 30, 2019 USD ($)
Real Estate Properties [Line Items]
Number of employees \| employee	0		0
Amended and restate business management agreement \| RMR LLC
Real Estate Properties [Line Items]
Number of management service agreements \| agreement	2		2
Business management fees incurred	$ 8,641	$ 9,919	$ 27,613	$ 29,307
Incentive fee calculation period			3 years
Related party property management and construction management fee	781	163	$ 2,722	201
Related party reimbursement expenses	$ 258	$ 136	$ 525	$ 478

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Represents the service agreements entered into by the entity for availing services from other entities.

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Related Party Property Management And Construction Management Fee And Construction Supervision

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Represents the business management fees incurred pursuant to business management agreement with related parties.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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