Related Person Transactions (Details) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($) agreement property investor jointVenture_arrangement shares
AlerisLife Inc
Related person transactions
Equity securities investment (in shares) \| shares	10,691,658
Investment owned, percentage of total shares outstanding	32.80%
RMR
Related person transactions
Number joint venture arrangements \| jointVenture_arrangement	2
Number of third party institutional investors \| investor	2
Number of medical office and life science properties \| property	10
Equity method investment ownership percentage	20.00%
Related rarty transaction, closing cost \| $	$ 11,113
Number of management agreements \| agreement	2
RMR \| Medical Office and Life Science Properties
Related person transactions
Number of medical office and life science properties \| property	10
Payments to related parties \| $	$ 185
AlerisLife Inc \| AlerisLife Inc
Related person transactions
Noncontrolling interest, ownership percentage by parent	6.20%

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Number Joint Venture Arrangements

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Number Of Third Party Institutional Investors

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Related Party, Management Agreements

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Related Party Transaction, Closing Cost

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Amount for accounts payable to related parties.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Balance held at close of period in number of shares.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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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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