Incentive Fees Payable Based On Common Share Total Return, Duration

No definition available.

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- Definition

Represents the number of agreements with RMR LLC to provide management services to the company.

+ References

No definition available.

+ Details

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- Definition

Represents the number of employees in the company.

+ References

No definition available.

+ Details

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- Definition

Total expense amount to reimburse a related party.

+ References

No definition available.

+ Details

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- Definition

Amount of expense for incentive rights held by the managing member or general partner, of limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- Definition

Amount paid for incentive rights held by the managing member or general partner, of limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3367-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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Balance Type:	credit
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

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

+ References

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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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Business and Property Management Agreements with RMR LLC (Details) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) agreement employee	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
RMR LLC
Related Party Transaction [Line Items]
Number of employees \| employee				0
Number of agreements \| agreement				2
Related party expense		$ 5,159	$ 20,575	$ 16,203	$ 30,059
Incentive fee (reversal)			16,236		16,973
Reimbursement expense		6,850	5,150	20,007	15,294
RMR LLC \| Net Property Management and Construction Supervision Fees
Related Party Transaction [Line Items]
Related party transaction amount		$ 5,622	$ 3,415	$ 16,605	$ 10,201
RMR LLC \| SIR \| Net Property Management and Construction Supervision Fees
Related Party Transaction [Line Items]
Payment for incentive fees	$ 2,185					$ 25,817
Affiliated entity \| RMR LLC
Related Party Transaction [Line Items]
Period of common share total return, incentive fees payable		3 years