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v3.20.2

Related Person Transactions - Additional Information (Details) - $ / shares | Sep. 30, 2020 | Feb. 13, 2020 | Sep. 30, 2019 | Jul. 01, 2019
--- | --- | --- | --- | ---
Related Party Transaction [Line Items] |  |  |  |
Common stock shares outstanding (in shares) | 15,000,000 |  | 15,000,000 |
ABP Trust | Class A common shares |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Common stock shares outstanding (in shares) | 157,502 |  |  |
ABP Trust | Class A units |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Common stock shares outstanding (in shares) | 15,000,000 |  |  |
Five Star |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Ownership percentage by noncontrolling owners | 6.40% |  |  |
SVC |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Ownership percentage by noncontrolling owners | 1.10% |  |  |
ILPT |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Ownership percentage by noncontrolling owners | 1.20% |  |  |
OPI |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Ownership percentage by noncontrolling owners | 1.50% |  |  |
DHC |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Ownership percentage by noncontrolling owners | 1.10% |  |  |
TA |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Ownership percentage by noncontrolling owners | 4.60% |  |  |
RMRM |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Ownership percentage by noncontrolling owners | 2.30% |  |  |
TRMT |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Ownership percentage by noncontrolling owners | 19.40% |  |  |
AIC | ABP Trust |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Ownership percentage by noncontrolling owners |  | 14.30% |  |
Centre Street | ABP Trust |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Ownership percentage by noncontrolling owners | 100.00% |  |  |
Underwritten Public Offering | DHC, OPI and SVC |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Number of shares issued (in dollars per share) |  |  |  | $ 40.00

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