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v3.20.2

Organization (Details) | 12 Months Ended
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Sep. 30, 2020 real_estate_investment_trust shares
Related Party Transaction [Line Items] |
Number of managed trusts | real_estate_investment_trust | 4
Class A membership units |
Related Party Transaction [Line Items] |
Anti-dilutive securities (in shares) | 15,000,000
Class A common shares | Class A membership units |
Related Party Transaction [Line Items] |
Membership units (in units) | 15,395,641
Class B-1 common shares |
Related Party Transaction [Line Items] |
Membership units (in units) | 1,000,000
ABP Trust | Class A membership units |
Related Party Transaction [Line Items] |
Membership units (in units) | 15,000,000
RMR LLC |
Related Party Transaction [Line Items] |
Ownership percentage | 52.20%
RMR LLC | ABP Trust | Redeemable Class A membership units |
Related Party Transaction [Line Items] |
Ownership percentage | 47.80%

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- Definition Number Of Managed Real Estate Investment Trusts + References No definition available. + Details
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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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