Business and Property Management Agreements with RMR LLC (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) employee agreement	Mar. 31, 2020 USD ($)
Real Estate Properties [Line Items]
Number of employees \| employee	0
RMR LLC
Real Estate Properties [Line Items]
Number of management service agreements \| agreement	2
Business management fees incurred	$ 10,299	$ 10,560
Incentive fee calculation period	3 years
Related party property management and construction management fee	$ 804	1,032
Related party reimbursement expenses	744	543
RMR LLC \| Property Management Fees
Real Estate Properties [Line Items]
Related party expenses	802	1,016
RMR LLC \| Construction and Supervision Fees Capitalized
Real Estate Properties [Line Items]
Related party transaction amount	$ 2	$ 16

Number of persons employed by the Entity

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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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Amount of transactions with related party during the financial reporting period.

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-Publisher FASB
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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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