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Related Person Transactions (Details)	Jun. 30, 2021 agreement shares
Five Star
Related person transactions
Equity securities investment (in shares) | shares	10,691,658
Investment owned, percentage of total shares outstanding	33.70%
RMR LLC
Related person transactions
Number of management agreements | agreement	2
RMR LLC | Five Star
Related person transactions
Investment owned, percentage of total shares outstanding	6.40%

X

- Definition

Represents the number of shares held as a percentage of the total shares outstanding at the end of the period.

+ References

No definition available.

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- Definition

Related Party, Management Agreements

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X

- Definition

Balance held at close of period in number of shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-12B(Column B))
-URI http://asc.fasb.org/extlink&oid=122147990&loc=d3e611197-123010

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- Definition

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.

+ References

No definition available.

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